Dissertations / Theses: 'Mobile mapping systems'

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Pereira, Savio Joseph. "On the utilization of Simultaneous Localization and Mapping(SLAM) along with vehicle dynamics in Mobile Road Mapping Systems." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/94425.

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Mobile Road Mapping Systems (MRMS) are the current solution to the growing demand for high definition road surface maps in wide ranging applications from pavement management to autonomous vehicle testing. The focus of this research work is to improve the accuracy of MRMS by using the principles of Simultaneous Localization and Mapping (SLAM). First a framework for describing the sensor measurement models in MRMS is developed. Next the problem of estimating the road surface from the set of sensor measurements is formulated as a SLAM problem and two approaches are proposed to solve the formulated problem. The first is an incremental solution wherein sensor measurements are processed in sequence using an Extended Kalman Filter (EKF). The second is a post-processing solution wherein the SLAM problem is formulated as an inference problem over a factor graph and existing factor graph SLAM techniques are used to solve the problem. For the mobile road mapping problem, the road surface being measured is one the primary inputs to the dynamics of the MRMS. Hence, concurrent to the main objective this work also investigates the use of the dynamics of the host vehicle of the system to improve the accuracy of the MRMS. Finally a novel method that builds off the concepts of the popular model fitting algorithm, Random Sampling and Consensus (RANSAC), is developed in order to identify outliers in road surface measurements and estimate the road elevations at grid nodes using these measurements. The developed methods are validated in a simulated environment and the results demonstrate a significant improvement in the accuracy of MRMS over current state-of-the art methods.<br>Doctor of Philosophy<br>Mobile Road Mapping Systems (MRMS) are the current solution to the growing demand for high definition road surface maps in wide ranging applications from pavement management to autonomous vehicle testing. The objective of this research work is to improve the accuracy of MRMS by investigating methods to improve the sensor data fusion process. The main focus of this work is to apply the principles from the field of Simultaneous Localization and Mapping (SLAM) in order to improve the accuracy of MRMS. The concept of SLAM has been successfully applied to the field of mobile robot navigation and thus the motivation of this work is to investigate its application to the problem of mobile road mapping. For the mobile road mapping problem, the road surface being measured is one the primary inputs to the dynamics of the MRMS. Hence this work also investigates whether knowledge regarding the dynamics of the system can be used to improve the accuracy. Also developed as part of this work is a novel method for identifying outliers in road surface datasets and estimating elevations at road surface grid nodes. The developed methods are validated in a simulated environment and the results demonstrate a significant improvement in the accuracy of MRMS over current state-of-the-art methods.

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Van, Tonder Bradley Paul. "Adaptive user interfaces for mobile map-based visualisation." Thesis, Nelson Mandela Metropolitan University, 2008. http://hdl.handle.net/10948/866.

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Mobile devices today frequently serve as platforms for the visualisation of map-based data. Despite the obvious advantages, mobile map-based visualisation (MMV) systems are often difficult to design and use. Limited screen space, resource constraints and awkward interaction mechanisms are among the many problems with which designers and users have to contend. Adaptive user interfaces (AUIs), which adapt to the individual user, represent a possible means of addressing the problems of MMV. Adaptive MMV systems are, however, generally designed in an ad-hoc fashion, making the benefits achieved difficult to replicate. In addition, existing models for adaptive MMV systems are either conceptual in nature or only address a subset of the possible input variables and adaptation effects. The primary objective of this research was to develop and evaluate an adaptive MMV system using a model-based approach. The Proteus Model was proposed to support the design of MMV systems which adapt in terms of information, visualisation and user interface in response to the user‟s behaviour, tasks and context. The Proteus Model describes the architectural, interface, data and algorithm design of an adaptive MMV system. A prototype adaptive MMV system, called MediaMaps, was designed and implemented based on the Proteus Model. MediaMaps allows users to capture, location-tag, organise and visualise multimedia on their mobile phones. Information adaptation is performed through the use of an algorithm to assist users in sorting media items into collections based on time and location. Visualisation adaptation is performed by adapting various parameters of the map-based visualisations according to user preferences. Interface adaptation is performed through the use of adaptive lists. An international field study of MediaMaps was conducted in which participants were required to use MediaMaps on their personal mobile phones for a period of three weeks. The results of the field study showed that high levels of accuracy were achieved by both the information and interface adaptations. High levels of user satisfaction were reported, with participants rating all three forms of adaptation as highly useful. The successful implementation of MediaMaps provides practical evidence that the model-based design of adaptive MMV systems is feasible. The positive results of the field study clearly show that the adaptations implemented were highly accurate and that participants found these adaptations to be useful, usable and easy to understand. This research thus provides empirical evidence that the use of AUIs can provide significant benefits for the visualisation of map-based information on mobile devices.

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Meger, David Paul. "Planning, localization, and mapping for a mobile robot in a camera network." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=101623.

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Networks of cameras such as building security systems can be a source of localization information for a mobile robot assuming a map of camera locations as well as calibration information for each camera is available. This thesis describes an automated system to acquire such information. A fully automated camera calibration system uses fiducial markers and a mobile robot in order to drastically improve ease-of-use compared to standard techniques. A 6DOF EKF is used for mapping and is validated experimentally over a 50 m hallway environment. Motion planning strategies are considered both in front of a single camera to maximize calibration accuracy and globally between cameras in order to facilitate accurate measurements. For global motion planning, an adaptive exploration strategy based on heuristic search allows compromise between distance traveled and final map uncertainty which provides the system a level of autonomy which could not be obtained with previous techniques.

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Van, Tonder Bradley Paul. "Enhanced sensor-based interaction techniques for mobile map-based applications." Thesis, Nelson Mandela Metropolitan University, 2012. http://hdl.handle.net/10948/d1012995.

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Mobile phones are increasingly being equipped with a wide range of sensors which enable a variety of interaction techniques. Sensor-based interaction techniques are particularly promising for domains such as map-based applications, where the user is required to interact with a large information space on the small screen of a mobile phone. Traditional interaction techniques have several shortcomings for interacting with mobile map-based applications. Keypad interaction offers limited control over panning speed and direction. Touch-screen interaction is often a two-handed form of interaction and results in the display being occluded during interaction. Sensor-based interaction provides the potential to address many of these shortcomings, but currently suffers from several limitations. The aim of this research was to propose enhancements to address the shortcomings of sensor-based interaction, with a particular focus on tilt interaction. A comparative study between tilt and keypad interaction was conducted using a prototype mobile map-based application. This user study was conducted in order to identify shortcomings and opportunities for improving tilt interaction techniques in this domain. Several shortcomings, including controllability, mental demand and practicality concerns were highlighted. Several enhanced tilt interaction techniques were proposed to address these shortcomings. These techniques were the use of visual and vibrotactile feedback, attractors, gesture zooming, sensitivity adaptation and dwell-time selection. The results of a comparative user study showed that the proposed techniques achieved several improvements in terms of the problem areas identified earlier. The use of sensor fusion for tilt interaction was compared to an accelerometer-only approach which has been widely applied in existing research. This evaluation was motivated by advances in mobile sensor technology which have led to the widespread adoption of digital compass and gyroscope sensors. The results of a comparative user study between sensor fusion and accelerometer-only implementations of tilt interaction showed several advantages for the use of sensor fusion, particularly in a walking context of use. Modifications to sensitivity adaptation and the use of tilt to perform zooming were also investigated. These modifications were designed to address controllability shortcomings identified in earlier experimental work. The results of a comparison between tilt zooming and Summary gesture zooming indicated that tilt zooming offered better results, both in terms of performance and subjective user ratings. Modifications to the original sensitivity adaptation algorithm were only partly successful. Greater accuracy improvements were achieved for walking tasks, but the use of dynamic dampening factors was found to be confusing. The results of this research were used to propose a framework for mobile tilt interaction. This framework provides an overview of the tilt interaction process and highlights how the enhanced techniques proposed in this research can be integrated into the design of tilt interaction techniques. The framework also proposes an application architecture which was implemented as an Application Programming Interface (API). This API was successfully used in the development of two prototype mobile applications incorporating tilt interaction.

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Sezginalp, Emre. "Simultaneous Localization And Mapping For A Mobile Robot Operating In Outdoor Environments." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/2/12609191/index.pdf.

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In this thesis, a method to the solution of autonomous navigation problem of a robot working in an outdoor application is sought. The robot will operate in unknown terrain where there is no a priori map present, and the robot must localize itself while simultaneously mapping the environment. This is known as Simultaneous Localization and Mapping (SLAM) problem in the literature. The SLAM problem is attempted to be solved by using the correlation between range data acquired at different poses of the robot. A robot operating outdoors will traverse unstructured terrain, therefore for localization, pitch, yaw and roll angles must also be taken into account along with the (x,y,z) coordinates of the robot. The Iterative Closest Points (ICP) algorithm is used to find this transformation between different poses of the robot and find its location. In order to collect the range data, a system composing of a laser range finder and an angular positioning system is used. During localization and mapping, odometry data is fused with range data.

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ROSA, STEFANO. "Localization and Mapping for Service Robotics Applications." Doctoral thesis, Politecnico di Torino, 2014. http://hdl.handle.net/11583/2542488.

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In this work we address different techniques for autonomous navigation of single and multi-robot systems in unstructured indoor environments. The first problem that we address is the problem of robot localization. We first show how a multi-robot localization approach can speed up the process as well as introducing robustness to failures. At the same time we show the possibility to introduce some sort of insight into the algorithm. We then focus on increasing the robustness of single robot localization, by taking advantage of sensor fusion and by exploiting visual markers embedded in the environment. We then show how the approach can be extended from ad-hoc markers to an arbitrary set of pre-existing objects already present in the environment. Then we address the more complicated problem of Simultaneous Localization and Mapping. In particular we focus on a promising technique called Graph-SLAM and we show the implementation of a front-end for this optimization technique in order to create a real online SLAM approach. The last part of the thesis is devoted to another part of service robotics which is not directly related to navigation: Human Robot Interaction (HRI). While this field of robotics is not strictly related to autonomous navigation, some part of it can be, such as the case of user following and object tracking. In Chapter 4 we discuss the implementation of an adaptive people tracking algorithm tailored for user tracking and following. We also show how this algorithm can easily be extended to the case of generic object tracking for human-robot cooperation.

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Paul, Rohan. "Long term appearance-based mapping with vision and laser." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:8d59bf8c-bec8-4782-b100-aa80d1136802.

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This thesis is about appearance-based topological mapping for mobile robots using vision and laser. Our goal is life-long continual operation in outdoor unstruc- tured workspaces. We present a new probabilistic framework for appearance-based mapping and navigation incorporating spatial and visual appearance. Locations are encoded prob- abilistically as random graphs possessing latent distributions over visual features and pair-wise euclidean distances generating observations modeled as 3D constellations of features observed via noisy range and visual detectors. Multi-modal distributions over inter-feature distances are learnt using non-parametric kernel density estima- tion. Inference is accelerated by executing a Delaunay tessellation of the observed graph with minimal loss in performance, scaling log-linearly with scene complexity. Next, we demonstrate how a robot can, through introspection and then targeted data retrieval, improve its own place recognition performance. We introduce the idea of a dynamic sampling set, the onboard workspace representation, that adapts with increasing visual experience of continually operating robot. Based on a topic based probabilistic model of images, we use a measure of perplexity to evaluate how well a working set of background images explains the robot’s online view of the world. O/ine, the robot then searches an external resource to seek additional background images that bolster its ability to localize in its environment when used next. Finally, we present an online and incremental approach allowing an exploring robot to generate apt and compact summaries of its life experience using canon- ical images that capture the essence of the robot’s visual experience-illustrating both what was ordinary and what was extraordinary. Leveraging probabilistic topic models and an incremental graph clustering technique we present an algorithm that scales well with time and variation of experience, generating a summary that evolves incrementally with the novelty of data.

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May, Nora Csanyi. "A rigorous approach to comprehesive performance analysis of state-of-the-art airborne mobile mapping systems." The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1199309957.

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May, Nora Csanyi. "A rigorous approach to comprehensive performance analysis of state-of-the-art airborne mobile mapping systems." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1199309957.

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Williams, Stefan Bernard. "Efficient Solutions to Autonomous Mapping and Navigation Problems." Thesis, The University of Sydney, 2001. http://hdl.handle.net/2123/809.

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This thesis deals with the Simultaneous Localisation and Mapping algorithm as it pertains to the deployment of mobile systems in unknown environments. Simultaneous Localisation and Mapping (SLAM) as defined in this thesis is the process of concurrently building up a map of the environment and using this map to obtain improved estimates of the location of the vehicle. In essence, the vehicle relies on its ability to extract useful navigation information from the data returned by its sensors. The vehicle typically starts at an unknown location with no a priori knowledge of landmark locations. From relative observations of landmarks, it simultaneously computes an estimate of vehicle location and an estimate of landmark locations. While continuing in motion, the vehicle builds a complete map of landmarks and uses these to provide continuous estimates of the vehicle location. The potential for this type of navigation system for autonomous systems operating in unknown environments is enormous. One significant obstacle on the road to the implementation and deployment of large scale SLAM algorithms is the computational effort required to maintain the correlation information between features in the map and between the features and the vehicle. Performing the update of the covariance matrix is of O(n3) for a straightforward implementation of the Kalman Filter. In the case of the SLAM algorithm, this complexity can be reduced to O(n2) given the sparse nature of typical observations. Even so, this implies that the computational effort will grow with the square of the number of features maintained in the map. For maps containing more than a few tens of features, this computational burden will quickly make the update intractable - especially if the observation rates are high. An effective map-management technique is therefore required in order to help manage this complexity. The major contributions of this thesis arise from the formulation of a new approach to the mapping of terrain features that provides improved computational efficiency in the SLAM algorithm. Rather than incorporating every observation directly into the global map of the environment, the Constrained Local Submap Filter (CLSF) relies on creating an independent, local submap of the features in the immediate vicinity of the vehicle. This local submap is then periodically fused into the global map of the environment. This representation is shown to reduce the computational complexity of maintaining the global map estimates as well as improving the data association process by allowing the association decisions to be deferred until an improved local picture of the environment is available. This approach also lends itself well to three natural extensions to the representation that are also outlined in the thesis. These include the prospect of deploying multi-vehicle SLAM, the Constrained Relative Submap Filter and a novel feature initialisation technique. Results of this work are presented both in simulation and using real data collected during deployment of a submersible vehicle equipped with scanning sonar.

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Althaus, Philipp. "Indoor Navigation for Mobile Robots : Control and Representations." Doctoral thesis, KTH, Numerical Analysis and Computer Science, NADA, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3644.

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<p>This thesis deals with various aspects of indoor navigationfor mobile robots. For a system that moves around in ahousehold or office environment,two major problems must betackled. First, an appropriate control scheme has to bedesigned in order to navigate the platform. Second, the form ofrepresentations of the environment must be chosen.</p><p>Behaviour based approaches have become the dominantmethodologies for designing control schemes for robotnavigation. One of them is the dynamical systems approach,which is based on the mathematical theory of nonlineardynamics. It provides a sound theoretical framework for bothbehaviour design and behaviour coordination. In the workpresented in this thesis, the approach has been used for thefirst time to construct a navigation system for realistic tasksin large-scale real-world environments. In particular, thecoordination scheme was exploited in order to combinecontinuous sensory signals and discrete events for decisionmaking processes. In addition, this coordination frameworkassures a continuous control signal at all times and permitsthe robot to deal with unexpected events.</p><p>In order to act in the real world, the control system makesuse of representations of the environment. On the one hand,local geometrical representations parameterise the behaviours.On the other hand, context information and a predefined worldmodel enable the coordination scheme to switchbetweensubtasks. These representations constitute symbols, on thebasis of which the system makes decisions. These symbols mustbe anchored in the real world, requiring the capability ofrelating to sensory data. A general framework for theseanchoring processes in hybrid deliberative architectures isproposed. A distinction of anchoring on two different levels ofabstraction reduces the complexity of the problemsignificantly.</p><p>A topological map was chosen as a world model. Through theadvanced behaviour coordination system and a proper choice ofrepresentations,the complexity of this map can be kept at aminimum. This allows the development of simple algorithms forautomatic map acquisition. When the robot is guided through theenvironment, it creates such a map of the area online. Theresulting map is precise enough for subsequent use innavigation.</p><p>In addition, initial studies on navigation in human-robotinteraction tasks are presented. These kinds of tasks posedifferent constraints on a robotic system than, for example,delivery missions. It is shown that the methods developed inthis thesis can easily be applied to interactive navigation.Results show a personal robot maintaining formations with agroup of persons during social interaction.</p><p><b>Keywords:</b>mobile robots, robot navigation, indoornavigation, behaviour based robotics, hybrid deliberativesystems, dynamical systems approach, topological maps, symbolanchoring, autonomous mapping, human-robot interaction</p>

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Gábrlík, Petr. "Bezpilotní průzkum prostředí v mobilní robotice." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-433633.

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Letecká fotogrammetrie v oblasti bezpilotních systémů představuje rychle rozvíjející se obor nalézající uplatnění napříč nejen průmyslovými odvětvími. Široce rozšířená metoda nepřímého georeferencování založená na vlícovacích bodech sice dosahuje vysoké přesnosti a spolehlivosti, v některých speciálních aplikacích nicméně není použitelná. Tato disertační práce se zabývá vývojem senzorického systému pro přímé georeferencování aplikovatelného na malých bezpilotních prostředcích a dále také návrhem vhodných kalibračních metod a testováním přesnosti. Významná část práce je věnována novým oblastem, kde může navržený systém pomoci eliminovat bezpečnostní rizika spojená s daným prostředím. V tomto kontextu byl systém testován v reálných podmínkách při mapování sněhu v horských oblastech a při robotickém mapování radiace.

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De, Marco Lisa. "Rilievo virtuale ad alto rendimento di pavimentazioni stradali: studio sperimentale per la valutazione di un indicatore sintetico di stato." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amslaurea.unibo.it/948/.

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Ceroni, Rodrigo. "Mobile Mapping System." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2016.

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Nella tesi si espone il Mobile Mapping System, cioè il rilevamento di dati geospaziali utilizzando sensori montati a bordo di appositi veicolo senza l'ausilio di punti di contatto a terra. Si illustrano i diversi dispositivi del sistema installati a bordo, le loro diverse applicazioni e metodologie di rilevamento. Si trattano le varie problematiche sorte e le loro risoluzioni.

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Nováčková, Soňa. "Testování přesnosti mobilního mapovacího systému MOMAS." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2012. http://www.nusl.cz/ntk/nusl-225361.

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The aim of this thesis is to introduce the mobile mapping system MOMAS, which is owned by Geodis Brno, spol. s.r.o. and test the accuracy of the system. Perform data collection and processing of data in the workplace company Geodis. In addition, identical target points, determine their coordinates and compare them with the coordinates obtained MOMAS system. And finally processed statistically derived coordinate differences.

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Ambrus, Rares. "Unsupervised construction of 4D semantic maps in a long-term autonomy scenario." Doctoral thesis, KTH, Centrum för Autonoma System, CAS, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-215323.

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Robots are operating for longer times and collecting much more data than just a few years ago. In this setting we are interested in exploring ways of modeling the environment, segmenting out areas of interest and keeping track of the segmentations over time, with the purpose of building 4D models (i.e. space and time) of the relevant parts of the environment. Our approach relies on repeatedly observing the environment and creating local maps at specific locations. The first question we address is how to choose where to build these local maps. Traditionally, an operator defines a set of waypoints on a pre-built map of the environment which the robot visits autonomously. Instead, we propose a method to automatically extract semantically meaningful regions from a point cloud representation of the environment. The resulting segmentation is purely geometric, and in the context of mobile robots operating in human environments, the semantic label associated with each segment (i.e. kitchen, office) can be of interest for a variety of applications. We therefore also look at how to obtain per-pixel semantic labels given the geometric segmentation, by fusing probabilistic distributions over scene and object types in a Conditional Random Field. For most robotic systems, the elements of interest in the environment are the ones which exhibit some dynamic properties (such as people, chairs, cups, etc.), and the ability to detect and segment such elements provides a very useful initial segmentation of the scene. We propose a method to iteratively build a static map from observations of the same scene acquired at different points in time. Dynamic elements are obtained by computing the difference between the static map and new observations. We address the problem of clustering together dynamic elements which correspond to the same physical object, observed at different points in time and in significantly different circumstances. To address some of the inherent limitations in the sensors used, we autonomously plan, navigate around and obtain additional views of the segmented dynamic elements. We look at methods of fusing the additional data and we show that both a combined point cloud model and a fused mesh representation can be used to more robustly recognize the dynamic object in future observations. In the case of the mesh representation, we also show how a Convolutional Neural Network can be trained for recognition by using mesh renderings. Finally, we present a number of methods to analyse the data acquired by the mobile robot autonomously and over extended time periods. First, we look at how the dynamic segmentations can be used to derive a probabilistic prior which can be used in the mapping process to further improve and reinforce the segmentation accuracy. We also investigate how to leverage spatial-temporal constraints in order to cluster dynamic elements observed at different points in time and under different circumstances. We show that by making a few simple assumptions we can increase the clustering accuracy even when the object appearance varies significantly between observations. The result of the clustering is a spatial-temporal footprint of the dynamic object, defining an area where the object is likely to be observed spatially as well as a set of time stamps corresponding to when the object was previously observed. Using this data, predictive models can be created and used to infer future times when the object is more likely to be observed. In an object search scenario, this model can be used to decrease the search time when looking for specific objects.<br><p>QC 20171009</p>

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Kintz, Andrew Lane. "Nullspace MUSIC and Improved Radio Frequency Emitter Geolocation from a Mobile Antenna Array." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1479896813925084.

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Chaplin, Bruce Alan. "Motion estimation from stereo image sequences for a mobile mapping system." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0020/MQ48058.pdf.

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Tavasci, Luca. "Metodi per l'ottimizzazione di rilievi Mobile Mapping System in aree urbane." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amslaurea.unibo.it/335/.

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Venený, Petr. "Detekce prostorových objektů v mračně bodů." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2019. http://www.nusl.cz/ntk/nusl-400180.

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The diploma thesis deals with processing of a point cloud that was collected via mobile mapping system. The first part sets a theoretical background, starting with mapping in general moving to mobile mapping systems and their particular parts. The practical part describes the whole process of data collecting, testing the automatic detection of spatial objects based on a point cloud and its visualisation. The results of the diploma thesis are GIS data layers and an evaluation of the process.

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Gomes, Pedro Miguel de Barros. "LADAR based mapping and obstacle detection system for service robots." Master's thesis, Faculdade de Ciências e Tecnologia, 2010. http://hdl.handle.net/10362/4589.

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Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para a obtenção do grau de Mestre em Engenharia Electrotécnica e de Computadores<br>When travelling in unfamiliar environments, a mobile service robot needs to acquire information about his surroundings in order to detect and avoid obstacles and arrive safely at his destination. This dissertation presents a solution for the problem of mapping and obstacle detection in indoor/outdoor structured3 environments, with particular application on service robots equipped with a LADAR. Since this system was designed for structured environments, offroad terrains are outside the scope of this work. Also, the use of any a priori knowledge about LADAR’s surroundings is discarded, i.e. the developed mapping and obstacle detection system works in unknown environments. In this solution, it is assumed that the robot, which carries the LADAR and the mapping and obstacle detection system, is based on a planar surface which is considered to be the ground plane. The LADAR is positioned in a way suitable for a three dimensional world and an AHRS sensor is used to increase the robustness of the system to variations on robot’s attitude, which, in turn, can cause false positives on obstacle detection. The results from the experimental tests conducted in real environments through the incorporation on a physical robot suggest that the developed solution can be a good option for service robots driving in indoor/outdoor structured environments.

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Barry, Jeremy Jude. "Map Creation and Position Correction for an Off the Shelf Mobile Robotic System." Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/33063.

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<p>Robots are widely used in domestic and commercial applications. These applications typically involve robots built for a specific the task, thus leading to efficiency in task completion. However, with the increase in completion efficiency comes an increase in the time required for completion of the whole system. Specific tasks create the need for many different robots, all with differing capabilities, causing an increase in development cost and time needed.<p> This raises the issue of whether using an off the shelf system with minor modifications can accurately perform the same tasks. If so, more time can be spent on refining the process leading to completion of the task, resulting in less time spent developing the robot. Consequently, less cost in the life cycle of the system leads to less cost for the end user, thus allowing robots to be used for more applications. <p> This thesis explores using a commercially available robot, Acroname Inc.â s Garcia, to perform mapping and localization tasks. As the robot travels it gathers data about the environment. This data is processed in Matlab and the result of the algorithm is a map. In the creation of the map, mathematical morphology is explored as a means to reduce noise. When the robot has located a corner, Matlab provides the robot with a position estimate correction. This correction allows the robot to better estimate its location resulting in a more accurate map. As the results of this thesis illustrate, with very minor modifications, the robot is capable of accurately performing mapping and localization tasks. The results demonstrate that an off the shelf system is capable of accurately performing tasks for which it was not specifically designed.<br>Master of Science

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Soheilian, Khorzoughi Bahman. "Roadmark reconstruction from stereo-images acquired by a ground-based mobile mapping system." Phd thesis, Université Paris-Est, 2008. http://tel.archives-ouvertes.fr/tel-00296601.

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Despite advances in ground-based Mobile Mapping System (MMS), automatic feature reconstruction seems far from being reached. In this thesis, we focus on 3D roadmark reconstruction from images acquired by road looking cameras of a MMS stereo-rig in dense urban context. A new approach is presented, that uses 3D geometric knowledge of roadmarks and provides a centimetric 3D accuracy with a low level of generalisation. Two classes of roadmarks are studied: zebra-crossing and dashed-lines. The general strategy consists in three main steps. The first step provides 3D linked-edges. Edges are extracted in the left and right images. Then a matching algorithm that is based on dynamic programming optimisation matches the edges between the two images. A sub-pixel matching is computed by post processing and 3D linked-edges are provided by classical photogrammetric triangulation. The second step uses the known specification of roadmarks to perform a signature based filtering of 3D linked-edges. This step provides hypothetical candidates for roadmark objects. The last step can be seen as a validation step that rejects or accepts the candidates. The validated candidates are finely reconstructed. The adopted model consists of a quasi parallelogram for each strip of zebra-crossing or dashed-line. Each strip is constrained to be flat but the roadmark as a whole is not planar. The method is evaluated on a set of 150 stereo-pairs acquired in a real urban area under normal traffic conditions. The results show the validity of the approach in terms of robustness, completeness and geometric accuracy. The method is robust and deals properly with partially occluded roadmarks as well as damaged or eroded ones. The detection rate reaches 90% and the 3D accuracy is about 2-4 cm. Finally an application of reconstructed roadmarks is presented. They are used in georeferencing of the system. Most of the MMSs use direct georeferencing devices such as GPS/INS for their localisation. However in urban areas masks and multi-path errors corrupt the measurements and provide only 50 cm accuracy. In order to improve the localisation quality, we aim at matching ground-based images with calibrated aerial images of the same area. For this purpose roadmarks are used as matching objects. The validity of this method is demonstrated on a zebra-crossing example

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Soheilian, Bahman. "Roadmark reconstruction from stereo-images acquired by a ground-based mobile mapping system." Thesis, Paris Est, 2008. http://www.theses.fr/2008PEST0260/document.

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Malgré les récentes avancées des Systèmes de Cartographie Mobile, la reconstruction automatique d’objets à partir des données acquises est encore un point crucial. Dans cette thèse, nous nous intéresserons en particulier à la reconstruction tridimensionnelle du marquage au sol à partir d’images acquises sur le réseau routier par une base stéréoscopique horizontale d’un système de cartographie mobile, dans un contexte urbain dense. Une nouvelle approche s’appuyant sur la connaissance de la géométrie 3D des marquages au sol est présentée, conduisant à une précision de reconstruction 3D centimétrique avec un faible niveau de généralisation. Deux objets de la signalisation routière horizontale sont étudiés : les passages piétons et les lignes blanches discontinues. La stratégie générale est composée de trois grandes étapes. La première d’entre elles permet d’obtenir des chaînes de contours 3D. Les contours sont extraits dans les images gauche et droite. Ensuite, un algorithme reposant sur une optimisation par programmation dynamique est mis en oeuvre pour apparier les points de contours des deux images. Un post-traitement permet un appariement sub-pixellique, et, les chaînes de contours 3D sont finalement obtenues par une triangulation photogrammétrique classique. La seconde étape fait intervenir les spécifications géométriques des marquages au sol pour réaliser un filtrage des chaînes de contours 3D. Elle permet de déterminer des candidats pour les objets du marquage au sol. La dernière étape peut être vue comme une validation permettant de rejeter ou d’accepter ces hypothèses. Les candidats retenus sont alors reconstruits finement. Pour chaque bande d’un passage piéton ou d’une ligne discontinue, le modèle est un quasi-parallélogramme. Une contrainte de planéité est imposée aux sommets de chaque bande, ce qui n’est pas le cas pour l’ensemble des bandes formant un marquage au sol particulier. La méthode est évaluée sur un ensemble de 150 paires d’images acquises en centre ville dans des conditions normales de trafic. Les résultats montrent la validité de notre stratégie en terme de robustesse, de complétude et de précision géométrique. La méthode est robuste et permet de gérer les occultations partielles ainsi que les marquages usés ou abîmés. Le taux de détection atteint 90% et la précision de reconstruction 3D est de l’ordre de 2 à 4 cm. Finalement, une application de la reconstruction des marquages au sol est présentée : le géoréférencement du système d’acquisition. La majorité des systèmes de cartographie mobile utilisent des capteurs de géoréférencement direct comme un couplage GPS/INS pour leur localisation. Cependant, en milieu urbain dense, les masques et les multi-trajets corrompent les mesures et conduisent à une précision d’environ 50 cm. Afin d’améliorer la qualité de localisation, nous cherchons à apparier les images terrestres avec des images aériennes calibrées de la même zone. Les marquages au sol sont alors utilisés comme objets d’appariement. La validité de la méthode est démontrée sur un exemple de passage piéton<br>Despite advances in ground-based Mobile Mapping System (MMS), automatic feature reconstruction seems far from being reached. In this thesis, we focus on 3D roadmark reconstruction from images acquired by road looking cameras of a MMS stereo-rig in dense urban context. A new approach is presented, that uses 3D geometric knowledge of roadmarks and provides a centimetric 3D accuracy with a low level of generalisation. Two classes of roadmarks are studied: zebra-crossing and dashed-lines. The general strategy consists in three main steps. The first step provides 3D linked-edges. Edges are extracted in the left and right images. Then a matching algorithm that is based on dynamic programming optimisation matches the edges between the two images. A sub-pixel matching is computed by post processing and 3D linked-edges are provided by classical photogrammetric triangulation. The second step uses the known specification of roadmarks to perform a signature based filtering of 3D linked-edges. This step provides hypothetical candidates for roadmark objects. The last step can be seen as a validation step that rejects or accepts the candidates. The validated candidates are finely reconstructed. The adopted model consists of a quasi parallelogram for each strip of zebra-crossing or dashed-line. Each strip is constrained to be flat but the roadmark as a whole is not planar. The method is evaluated on a set of 150 stereo-pairs acquired in a real urban area under normal traffic conditions. The results show the validity of the approach in terms of robustness, completeness and geometric accuracy. The method is robust and deals properly with partially occluded roadmarks as well as damaged or eroded ones. The detection rate reaches 90% and the 3D accuracy is about 2-4 cm. Finally an application of reconstructed roadmarks is presented. They are used in georeferencing of the system. Most of the MMSs use direct georeferencing devices such as GPS/INS for their localisation. However in urban areas masks and multi-path errors corrupt the measurements and provide only 50 cm accuracy. In order to improve the localisation quality, we aim at matching ground-based images with calibrated aerial images of the same area. For this purpose roadmarks are used as matching objects. The validity of this method is demonstrated on a zebra-crossing example

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Marastoni, Diego. "Metodi matematici e statistici finalizzati al rilievo di precisione mediante SISTEMI MOBILE MAPPING SYSTEM." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amslaurea.unibo.it/333/.

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Al, Shaiba Omar. "Update urban basemap by using the LiDAR mobile mapping system : the case of Abu Dhabi municipal system." Doctoral thesis, Universitat Politècnica de Catalunya, 2020. http://hdl.handle.net/10803/669771.

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Basemaps are the main resource used in urban planning and in building and infrastructure asset management. These maps are used by citizens and by private and public stakeholders. Therefore, accurate, up-to-date geoinformation of reference are needed to provide a good service. In general, basemaps have been updated by aerial photogrammetry or field surveying, but these methods are not always possible and alternatives need to be sought. Current limitations and challenges that face traditional field surveys include areas with extreme weather, deserts or artic environments, and flight restrictions due to proximity with other countries if there is not an agreement. In such cases, alternatives for large-scale are required. This thesis proposes the use of a mobile mapping system (MMS) to update urban basemaps. Most urban features can be extracted from point cloud using commercial software or open libraries. However, there are some exceptions: manhole covers, or hidden elements even with captures from defferent perspective, the most common building corners. Therefore, the main objective of this study was to establish a methodology for extracting manholes automatically and for completing hidden corners of buildings, so that urban basemaps can be updated. The algorithm developed to extract manholes is based on time, intensity and shape detection parameters, whereas additional information from satellite images is used to complete buildings. Each municipality knows the materials and dimensions of its manholes. Taking advantage of this knowledge, the point cloud is filtered to classify points according to the set of intensity values associated with the manhole material. From the classified points, the minimum bounding rectangles (MBR) are obtained and finally the shape is adjusted and drawn. We use satellite imagery to automatically digitize the layout of building footprints with automated software tools. Then, the visible corners of buildings from the LiDAR point cloud are imported and a fitting process is performed by comparing them with the corners of the building from the satellite image. Two methods are evaluated to establish which is the most suitable for adjustment in these conditions. In the first method, the differences in X and Y directions are measured in the corners, where LiDAR and satellite data are available, and is often computed as the average of the offsets. In the second method, a Helmert 2D transformation is applied. MMS involves Global Navigation Satellite Systems (GNSS) and Inertial Measurement Units (IMU) to georeference point clouds. Their accuracy depends on the acquisition environment. In this study, the influence of the urban pattern is analysed in three zones with varied urban characteristics: different height buildings, open areas, and areas with a low and high level of urbanization. To evaluate the efficiency of the proposed algorithms, three areas were chosen with varying urban patterns in Abu Dhabi. In these areas, 3D urban elements (light poles, street signs, etc) were automatically extracted using commercial software. The proposed algorithms were applied to the manholes and buildings. The completeness and correctness ratio, and geometric accuracy were calculated for all urban elements in the three areas. The best success rates (>70%) were for light poles, street signs and road curbs, regardless of the height of the buildings. The worst rate was obtained for the same features in peri-urban areas, due to high vegetation. In contrast, the best results for trees were found in theses areas. Our methodology demonstrates the great potential and efficiency of mobile LiDAR technology in updating basemaps; a process that is required to achieve standard accuracy in large scale maps. The cost of the entire process and the time required for the proposed methodology was calculated and compared with the traditional method. It was found that mobile LiDAR could be a standard cost-efficient procedure for updating maps.<br>La cartografía de referencia es la principal herramienta en planificación urbanística, y gestión de infraestructuras y edificios, al servicio de ciudadanos, empresas y administración. Por esta razón, debe estar actualizada y ser lo más precisa posible. Tradicionalmente, la cartografía se actualiza mediante fotogrametría aérea o levantamientos terrestres. No obstante, deben buscarse alternativas válidas para escalas grandes, porque no siempre es posible emplear estas técnicas debido a las limitaciones y retos actuales a los que se enfrenta la medición tradicional en algunas zonas del planeta, con meteorología extrema o restricciones de vuelo por la proximidad a la frontera con otros países. Esta tesis propone el uso del sistema Mobile Mapping System (MMS) para actualizar la cartografía urbana de referencia. La mayoría de los elementos pueden extraerse empleando software comercial o librerías abiertas, excepto los registros de servicios. Los elementos ocultos son otro de los inconvenientes encontrados en el proceso de creación o actualización de la cartografía, incluso si se dispone de capturas desde diferentes puntos de vista. El caso más común es el de las esquinas de edificios. Por ello, el principal objetivo de este estudio es establecer una metodología de extracción automática de los registros y completar las esquinas ocultas de los edificios para actualizar cartografía urbana. El algoritmo desarrollado para la detección y extracción de registros se basa en parámetros como el tiempo, la intensidad de la señal laser y la forma de los registros, mientras que para completar los edificios se emplea información adicional de imágenes satélite. Aprovechando el conocimiento del material y dimensión de los registros, en disposición de los gestores municipales, el algoritmo propuesto filtra y clasifica los puntos de acuerdo a los valores de intensidad. De aquellos clasificados como registros se calcula el mínimo rectángulo que los contiene (Minimum Bounding Rectangle) y finalmente se ajusta la forma y se dibuja. Las imágenes de satélite son empleadas para obtener automáticamente la huella de los edificios. Posteriormente, se importan las esquinas visibles de los edificios obtenidas desde la nube de puntos y se realiza el ajuste comparándolas con las obtenidas desde satélite. Para llevar a cabo este ajuste se han evaluado dos métodos, el primero de ellos considera las diferencias entre las coordenadas XY, desplazándose el promedio. En el segundo, se aplica una transformación Helmert2D. MMS emplea sistemas de navegación global por satélite (Global Navigation Satellite Systems, GNSS) e inerciales (Inertial Measurement Unit, IMU) para georreferenciar la nube de puntos. La precisión de estos sistemas de posicionamiento depende del entorno de adquisición. Por ello, en este estudio se han seleccionado tres áreas con distintas características urbanas (altura de edificios, nivel de urbanización y áreas abiertas) de Abu Dhabi con el fin de analizar su influencia, tanto en la captura, como en la extracción de los elementos. En el caso de farolas, señales viales, árboles y aceras se ha realizado con software comercial, y para registros y edificios con los algoritmos propuestos. Las ratios de corrección y completitud, y la precisión geométrica se han calculado en las diferentes áreas urbanas. Los mejores resultados se han conseguido para las farolas, señales y bordillos, independientemente de la altura de los edificios. La peor ratio se obtuvo para los mismos elementos en áreas peri-urbanas, debido a la vegetación. Resultados opuestos se han conseguido en la detección de árboles. El coste económico y en tiempo de la metodología propuesta resulta inferior al de métodos tradicionales. Lo cual demuestra el gran potencial y eficiencia de la tecnología LiDAR móvil para la actualización cartografía de referencia

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Manda, David. "Mobilní mapování." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-226350.

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The aim of this thesis is introduce the mobile mapping system IP-S2, which is using by company GEODIS BRNO, and perform data collection by this system. Measure the identical points, determine their coordinates and compare with coordinates obtained by mobile mapping system. The conclusion of this thesis is focused on testing the accuracy of the mobile mapping system.

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Duque, Fredd. "Six DOF tracking system based on smartphones internal sensors for standalone mobile VR." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-260345.

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Nowadays mid-range smartphones have enough computational power to run simultaneous location and mapping (SLAM) algorithms that, together with their onboard inertial sensors makes them capable of position and rotation tracking. Based on this, Google and Apple have released their own respective software development kits (SDKs) that allow smartphones to run augmented reality applications using six degrees of freedom tracking. However, this same approach could be implemented to virtual reality head-mounted-display (HMD) based on smartphones, but current virtual reality SDKs only offer rotational tracking. In this study the positional tracking technology used for augmented reality mobile applications has been implemented in a virtual reality head-mounted-display only powered by a smartphone by combining virtual and augmented reality SDKs. Compatibility issues between SDKs have been faced to develop a working prototype. An objective and controlled measurement study has been conducted that included 34.200 measurements, to test the accuracy, precision and jitter tracking of the protype against the Oculus Rift, a dedicated virtual reality system. Results show that the developed prototype offers a decent tracking precision and accuracy in optimal conditions. It was concluded to be highly dependent on the camera view. Although, jitter presented the opposite behavior, being dependent to the device used but independent on the camera view. In its optimal conditions, user studies demonstrated that the prototype was capable of offering the same tracking performance feeling as the Oculus Rift although jitter was quite noticeable, and a common user complain. Further studies are proposed that can improve the tracking performance of the prototype by filtering jitter and using two or more cameras with a different angular to correlate feature points and obtain a wider view of the environment were the prototype is used.<br>Idag har mellanklass-smartphones tillräckligt med beräkningskapacitet för att simultant köra lokalisering och kartläggnings(SLAM) algoritmer tillsammans med deras tröghetssensorer ombord, vilket gör att de kan positionera och rotera spårning. Baserat på det här så har Google och Apple släppt sina egna respektive programvaror (SDK) som gör att smartphones kan köra ökade realitetsapplikationer med sex graders frihetsspårning. Emellertid kan samma tillvägagångssätt implementeras till virtuell verklighet på en huvudmonterad display (HMD) baserat på smartphones, men nuvarande VR SDK erbjuder endast rotationsspårning. I denna studie så har positionell spårningsteknik som används för AR i mobila applikationer implementerats i ett VRheadset som endast drivs av en smartphone genom att kombinera VR och ARSDKs. Kompatibilitetsproblem mellan SDKs har resulterat i att utveckla en fungerande prototyp. En objektiv och kontrollerad mätstudie har genomförts som inkluderade 34.200 mätningar, för att testa noggrannheten, precision och jitterspårning av protyp mot Oculus Rift, ett dedikerat virtuellt verklighetssystem. Resultat visar att den utvecklade prototypen ger en anständig spårningsprecision och noggrannhet i optimala betingelser. Denna slutsats var mycket beroende av kameravy. Även om jitter presenterade det motsatta beteendet, beroende på vilken enhet som används men oberoende av kamerans vy. I sina optimala förhållanden visade användarstudier att prototypen kunde erbjuda samma spårningsförmåga som Oculus Rift, även om jitter var ganska märkbar, och en vanlig användares klagomål. Ytterligare studier föreslås som kan förbättra prototypens spårningsprestanda genom att filtrera jitter och använder två eller flera kameror med en annan vinkling till att korrelera funktionspunkter och få en bredare bild av miljön var prototypen används.

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Capucci, Laura. "Analisi di rilievi con mobile mapping system per lo sviluppo di un sistema informatizzato di gestione integrata delle pavimentazioni stradali." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amslaurea.unibo.it/2038/.

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Hoffmannová, Lada. "Testování přesnosti mobilního laserového skenování." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2020. http://www.nusl.cz/ntk/nusl-414306.

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Diploma thesis describes collecting of data by mobile mapping system Riegl VMX-450. Science centre AdMas was captured with mobile mapping system. For the purpose of testing the accuracy, a calibration field was constructed in AdMaS. Main part of the thesis deals with testing of the accuracy of point cloud. Calibration field's coordinates were obtained by adjustment of the geodetic network using the least squares adjustment. During the testing, the coordinates of the calibration field points determined by the adjustment of the geodetic network and the coordinates of the points determined from the point cloud were compared. Another part of the work deals with testing of the accuracy, when target's position is in different height levels.

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Poreba, Martyna. "Qualification et amélioration de la précision de systèmes de balayage laser mobiles par extraction d’arêtes." Thesis, Paris, ENMP, 2014. http://www.theses.fr/2014ENMP0012/document.

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Au cours de ces dernières décennies, le développement de Systèmes Mobiles de Cartographie, soutenu par un progrès technologique important, est devenu plus apparent. Il a été stimulé par le besoin grandissant de collecte d'informations géographiques précises sur l'environnement. Nous considérons, au sein de cette thèse, des solutions pour l'acquisition des nuages de points mobiles de qualité topographique (précision centimétrique). Il s'agit, dans cette tâche, de mettre au point des méthodes de qualification des données, et d'en améliorer sur les erreurs systématiques par des techniques d'étalonnage et de recalage adéquates.Nous décrivons une démarche innovante d'évaluation de l'exactitude et/ou de la précision des relevés laser mobiles. Celle-ci repose sur l'extraction et la comparaison des entités linéaires de la scène urbaine. La distance moyenne calculée entre les segments appariés, étant la distance modifiée de Hausdorff, sert à noter les nuages par rapport à des références existantes. Pour l'extraction des arêtes, nous proposons une méthode de détection d'intersections entre segments plans retrouvés via un algorithme de RANSAC enrichi d'une analyse de composantes connexes. Nous envisageons également une démarche de correction de relevés laser mobiles à travers un recalage rigide fondé, lui aussi, sur les éléments linéaires. Enfin, nous étudions la pertinence des segments pour en déduire les paramètres de l'étalonnage extrinsèque du système mobile. Nous testons nos méthodes sur des données simulées et des données réelles acquises dans le cadre du projet TerraMobilita<br>Over the past few decades, the development of land-based Mobile Mapping Systems (MMS), supported by significant technological progress, has become more prominent. It has been motivated by the growing need for precise geographic information about the environment. In this thesis, we consider approaches for the acquisition of mobile point clouds with topographic quality (centimeter-level accuracy). The aim is to develop techniques for data quality assessment and improvement. In particular, we eliminate the systematic errors inherent to an MMS data using appropriate calibration and registration methods.We describe a novel approach to assess the accuracy and/or the precision of mobile laser point clouds. It is based on the extraction and comparison of line features detected within the urban scene. The computed average distance between corresponding pairs of line segments, taking advantage of a modified Hausdorff distance, is used to evaluate the MMS data with respect to a reference data set. For edge extraction, we propose a method which relies on the intersections between planes modelled via the RANSAC algorithm refined by an analysis of connected components. We also consider an approach to correct point clouds using a line-based rigid registration method. Finally, we study the use of line segments for estimating the boresight angles of a land-based mobile mapping system. We apply our methods to synthetic data and to real data acquired as part of the TerraMobilita project

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Nováková, Věra. "Vypracování metodik pro tvorbu informačního modelu budovy." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-227099.

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This thesis is focused on creation of building information model (BIM) for existing buildings. The main objective of this work is to develop the methodology (workflow) for the creation of BIM model using selected geodetic methods, specifically for the modeling based on the existing documentation of the building, the modeling from the handheld distance meter and the modeling from point cloud acquired by the indoor mapping system. The aim of these workflows is to explore the suitability of these methods, to check the limits of each method and to point out the potential issues. Revit (version 2013 and 2014) was used as an authoring environment for creation of the models. Workflow for modeling based on the documentation of the building shows how to insert drawings into Revit and how to create a model based on these drawings. The workflow was developed based on experience with creation of model of an office building. The workflow for handheld laser distance meter describes how to work with rangefinder equipped with Bluetooth, which allows user to create a model onsite. The third part of this thesis deals with creation of BIM from pointcloud acquired by indoor mobile mapping system. The workflow describes data collection and point clouds processing directly in Revit using the ScanToBIM extension. The results of this work are methodical instructions for the methods described above and the comparison of these methods. Workflows contain recommended procedures and highlight common issues and mistakes. This should enable the readers of this thesis to choose the right method and avoid common mistakes.

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Huang, Henry. "Bearing-only SLAM : a vision-based navigation system for autonomous robots." Thesis, Queensland University of Technology, 2008. https://eprints.qut.edu.au/28599/1/Henry_Huang_Thesis.pdf.

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To navigate successfully in a previously unexplored environment, a mobile robot must be able to estimate the spatial relationships of the objects of interest accurately. A Simultaneous Localization and Mapping (SLAM) sys- tem employs its sensors to build incrementally a map of its surroundings and to localize itself in the map simultaneously. The aim of this research project is to develop a SLAM system suitable for self propelled household lawnmowers. The proposed bearing-only SLAM system requires only an omnidirec- tional camera and some inexpensive landmarks. The main advantage of an omnidirectional camera is the panoramic view of all the landmarks in the scene. Placing landmarks in a lawn field to define the working domain is much easier and more flexible than installing the perimeter wire required by existing autonomous lawnmowers. The common approach of existing bearing-only SLAM methods relies on a motion model for predicting the robot’s pose and a sensor model for updating the pose. In the motion model, the error on the estimates of object positions is cumulated due mainly to the wheel slippage. Quantifying accu- rately the uncertainty of object positions is a fundamental requirement. In bearing-only SLAM, the Probability Density Function (PDF) of landmark position should be uniform along the observed bearing. Existing methods that approximate the PDF with a Gaussian estimation do not satisfy this uniformity requirement. This thesis introduces both geometric and proba- bilistic methods to address the above problems. The main novel contribu- tions of this thesis are: 1. A bearing-only SLAM method not requiring odometry. The proposed method relies solely on the sensor model (landmark bearings only) without relying on the motion model (odometry). The uncertainty of the estimated landmark positions depends on the vision error only, instead of the combination of both odometry and vision errors. 2. The transformation of the spatial uncertainty of objects. This thesis introduces a novel method for translating the spatial un- certainty of objects estimated from a moving frame attached to the robot into the global frame attached to the static landmarks in the environment. 3. The characterization of an improved PDF for representing landmark position in bearing-only SLAM. The proposed PDF is expressed in polar coordinates, and the marginal probability on range is constrained to be uniform. Compared to the PDF estimated from a mixture of Gaussians, the PDF developed here has far fewer parameters and can be easily adopted in a probabilistic framework, such as a particle filtering system. The main advantages of our proposed bearing-only SLAM system are its lower production cost and flexibility of use. The proposed system can be adopted in other domestic robots as well, such as vacuum cleaners or robotic toys when terrain is essentially 2D.

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Huang, Henry. "Bearing-only SLAM : a vision-based navigation system for autonomous robots." Queensland University of Technology, 2008. http://eprints.qut.edu.au/28599/.

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To navigate successfully in a previously unexplored environment, a mobile robot must be able to estimate the spatial relationships of the objects of interest accurately. A Simultaneous Localization and Mapping (SLAM) sys- tem employs its sensors to build incrementally a map of its surroundings and to localize itself in the map simultaneously. The aim of this research project is to develop a SLAM system suitable for self propelled household lawnmowers. The proposed bearing-only SLAM system requires only an omnidirec- tional camera and some inexpensive landmarks. The main advantage of an omnidirectional camera is the panoramic view of all the landmarks in the scene. Placing landmarks in a lawn field to define the working domain is much easier and more flexible than installing the perimeter wire required by existing autonomous lawnmowers. The common approach of existing bearing-only SLAM methods relies on a motion model for predicting the robot’s pose and a sensor model for updating the pose. In the motion model, the error on the estimates of object positions is cumulated due mainly to the wheel slippage. Quantifying accu- rately the uncertainty of object positions is a fundamental requirement. In bearing-only SLAM, the Probability Density Function (PDF) of landmark position should be uniform along the observed bearing. Existing methods that approximate the PDF with a Gaussian estimation do not satisfy this uniformity requirement. This thesis introduces both geometric and proba- bilistic methods to address the above problems. The main novel contribu- tions of this thesis are: 1. A bearing-only SLAM method not requiring odometry. The proposed method relies solely on the sensor model (landmark bearings only) without relying on the motion model (odometry). The uncertainty of the estimated landmark positions depends on the vision error only, instead of the combination of both odometry and vision errors. 2. The transformation of the spatial uncertainty of objects. This thesis introduces a novel method for translating the spatial un- certainty of objects estimated from a moving frame attached to the robot into the global frame attached to the static landmarks in the environment. 3. The characterization of an improved PDF for representing landmark position in bearing-only SLAM. The proposed PDF is expressed in polar coordinates, and the marginal probability on range is constrained to be uniform. Compared to the PDF estimated from a mixture of Gaussians, the PDF developed here has far fewer parameters and can be easily adopted in a probabilistic framework, such as a particle filtering system. The main advantages of our proposed bearing-only SLAM system are its lower production cost and flexibility of use. The proposed system can be adopted in other domestic robots as well, such as vacuum cleaners or robotic toys when terrain is essentially 2D.

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GRASSO, NIVES. "Visibility analyses using 3D urban models generated by low-cost multi-sensor approaches." Doctoral thesis, Politecnico di Torino, 2018. http://hdl.handle.net/11583/2705900.

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The conditions of visibility of a user moving through an outdoor or indoor environment affect his safety. In both environments it is fundamental to guarantee a sufficient visibility in order to avoid possible collisions. In the specific case of urban roads the available sight distance (ASD) is that part of the roadway ahead which is visible to the driver and should be of sufficient length to allow a vehicle to stop before colliding with a stationary object. Unfortunately, the estimation of the ASD is still carried out on 2D maps or digital terrain models (DTM). Furthermore, it is very complicated to estimate the ASD on urban roads due to difficulties in measuring the effects of individual sight obstructions in a context where their density and dynamicity is relatively high. It is obvious that a 3D representation of the infrastructure may offer more flexibility when modeling sight obstructions and in capturing the complexity of the urban context. Different consideration must to be made for indoor environment, in which, in particular for public buildings, it is important that the main escape routes are correctly signalized. In these situations, a large number of people must easily flow even in highly articulated environments. It is necessary to identify the easiest paths to follow in order to ensure a fast and efficient escape route. The ways in which a person is able to move within the environment are strongly influenced by the space he is able to see in front of himself. The indoor geometry of buildings and the position of some objects can limits the visibility, affecting the perception of the paths through which it is possible to navigate. Different methods have been analyzed to identify the visible space from a certain point of view, by linking the user's perception with the surrounding environment. However, many of these studies are aimed at a two-dimensional environment analysis, or do not take into account a possible dynamic configuration of the motion. The aim of this research work is to propose automatic methods for the visibility analysis, indoor and outdoor, that take into account the dynamism of the individual and the environment. Since it is essential to have a 3D model on which to base the analyses, the first part of the research, will be focused on the investigation of rapid and flexible survey methods, capable of adapting to different contexts of interest. Today the geomatics field already offers different solutions and technologies for collecting 3D information of objects or environments at different scales. In recent years, the development of mobile mapping systems (MMS) that integrate active, passive and positioning sensors, has made a substantial increase in applications in the close-range domain. Moreover, the growth of software solutions for the extraction of point clouds from non-metric image sets has obtained great attention; in fact, these systems combine a good quality of results, both from a metric and a qualitative point of view, simplicity in their use and their accessibility, thanks also to the various free and open source solutions. The main issue regarding the existing MMSs is the high cost of these technologies, which limits their use. A goal of this work is related to evaluate the possibility to realize and to use low-cost MMSs as an alternative for obtaining 3D information of urban infrastructure. Here the term MMS is used in its broadest meaning, considering MMSs all those mapping systems that can be mounted on any type of mobile platform (aerial or terrestrial). In particular, low-cost MMSs mounted on a vehicle or bicycle or carried out by a pedestrian (such as backpacks) will be proposed. Today the mass-market offers a wide choice of low-cost sensors for image acquisition and positioning. Among the imaging sensors, it is possible to find webcams, action-cams and other solutions that can capture high-resolution images while maintaining a very small size and weight. However, these sensors are born with different purposes from the photogrammetric one and, therefore, their use must necessarily be preceded by an analysis of their intrinsic characteristics and their performances and limits under different conditions of use. Starting from these assumptions, the characteristics of multiple low-cost imaging sensors (an action-cam Garmin Virb Elite, Logitech HD Pro Webcams C920, Raspberry Pi Camera Modules v2 and a panoramic camera NCTech iSTAR Fusion) and their intrinsic parameters have been evaluated. Subsequently, after the realization of different tools for the management of the sensors, their synchronization in time and the data storage, some tests were performed in an urban environment in order to evaluate the performances of different configurations of low-cost MMSs and the accuracies of the obtainable 3D models. The input data used for the 3D information extraction were video and frames, which were processed through Structure from Motion (Sfm) technique. The second part of the activities aimed at the development of automatic procedures to perform visibility analysis exploiting the obtained 3D model of the environment. Different tools for the visibility analysis and the estimation of the ASD from a driver’s point of view were compiled and tested. These approaches aimed at identifying all the objects that obstruct the sight of the driver along the road infrastructure. The visibility analyses were performed through ArcGIS and Matlab® tools using the Line of Sight (LoS) approach, and taking into account the dynamicity of the movement. Finally, a procedure for quantitatively assessing the complexity of a known path to follow in emergency cases inside of public buildings was proposed. The methodology combines the use of isovists and visibility graphs techniques and allows to extract numerical descriptors of the environment.

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Biasutti, Pierre. "2D Image Processing Applied to 3D LiDAR Point Clouds." Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0161/document.

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L'intérêt toujours grandissant pour les données cartographiques fiables, notamment en milieu urbain, a motivé le développement de systèmes de cartographie mobiles terrestres. Ces systèmes sont conçus pour l'acquisition de données de très haute précision, telles que des nuages de points LiDAR 3D et des images optiques. La multitude de données, ainsi que leur diversité, rendent complexe le traitement des données issues de ce type de systèmes. Cette thèse se place dans le contexte du traitement de l'image appliqué au nuages de points LiDAR 3D issus de ce type de système.Premièrement, nous nous intéressons à des images issues de la projection de nuages de points LiDAR dans des grilles de pixels 2D régulières. Ces projections créent généralement des images éparses, dans lesquelles l'information de certains pixels n'est pas connue. Nous proposons alors différentes méthodes pour des applications telles que la génération d'orthoimages haute résolution, l'imagerie RGB-D et l'estimation de la visibilité des points d'un nuage.De plus, nous proposons d'exploiter la topologie d'acquisition des capteurs LiDAR pour produire des images de faible résolution: les range-images. Ces images offrent une représentation efficace et canonique du nuage de points, tout en étant directement accessibles à partir du nuage de points. Nous montrons comment ces images peuvent être utilisées pour simplifier, voire améliorer, des méthodes pour le recalage multi-modal, la segmentation, la désoccultation et la détection 3D<br>The ever growing demand for reliable mapping data, especially in urban environments, has motivated the development of "close-range" Mobile Mapping Systems (MMS). These systems acquire high precision data, and in particular 3D LiDAR point clouds and optical images. The large amount of data, along with their diversity, make MMS data processing a very complex task. This thesis lies in the context of 2D image processing applied to 3D LiDAR point clouds acquired with MMS.First, we focus on the projection of the LiDAR point clouds onto 2D pixel grids to create images. Such projections are often sparse because some pixels do not carry any information. We use these projections for different applications such as high resolution orthoimage generation, RGB-D imaging and visibility estimation in point clouds.Moreover, we exploit the topology of LiDAR sensors in order to create low resolution images, named range-images. These images offer an efficient and canonical representation of the point cloud, while being directly accessible from the point cloud. We show how range-images can be used to simplify, and sometimes outperform, methods for multi-modal registration, segmentation, desocclusion and 3D detection

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Saad, Sawsan. "Conception et Optimisation Distribuée d’un Système d’Information des Services d’Aide à la Mobilité Urbaine Basé sur une Ontologie Flexible dans le Domaine de Transport." Thesis, Ecole centrale de Lille, 2010. http://www.theses.fr/2010ECLI0017/document.

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De nos jours, les informations liées au déplacement et à la mobilité dans un réseau de transport représentent sans aucun doute un potentiel important.Ces travaux visent à mettre en œuvre un Système d’Information de Service d’Aide à la Mobilité Urbaine (SISAMU).Le SISAMU doit pouvoir procéder par des processus de décomposition des requêtes simultanées en un ensemble de tâches indépendantes. Chaque tâche correspond à un service qui peut être proposé par plusieurs fournisseurs d’information en concurrence, avec différents coûts, temps de réponse et formats. Le SISAMU est lié à un Réseau informatique Etendu et distribué de Transport Multimodal (RETM) qui comporte plusieurs sources d’information hétérogènes des différents services proposés aux utilisateurs de transport. L’aspect dynamique, distribué et ouvert du problème, nous a conduits à adopter une modélisation multi-agent pour assurer au système une évolution continue et une flexibilité pragmatique. Pour ce faire, nous avons proposé d’automatiser la modélisation des services en utilisant la notion d’ontologie. Notre SISAMU prend en considération les éventuelles perturbations sur le RETM.Ansi, nous avons créé un protocole de négociation entre les agents. Le protocole de négociation proposé qui utilise l’ontologie de la cartographie se base sur un système de gestion des connaissances pour soutenir l'hétérogénéité sémantique. Nous avons détaillé l’Algorithme de Reconstruction Dynamique des Chemins des Agents (ARDyCA) qui est basé sur l’approche de l’ontologie cartographique. Finalement, les résultats présentés dans cette thèse justifient l’utilisation de l’ontologie flexible et son rôle dans le processus de négociation<br>Nowadays, information related on displacement and mobility in a transport network represents certainly a significant potential. So, this work aims to modeling, to optimize and to implement an Information System of Services to Aid the Urban Mobility (ISSAUM).The ISSAUM has firstly to decompose each set of simultaneous requests into a set of sub-requests called tasks. Each task corresponds to a service which can be proposed different by several information providers with different. An information provider which aims to propose some services through our ISSAUM has to register its ontology. Indeed, ISSAUM is related to an Extended and distributed Transport Multimodal Network (ETMN) which contains several heterogeneous data sources. The dynamic and distributed aspects of the problem incite us to adopt a multi-agent approach to ensure a continual evolution and a pragmatic flexibility of the system. So, we proposed to automate the modeling of services by using ontology idea. Our ISSAUM takes into account possible disturbance through the ETMN. In order to satisfy user requests, we developed a negotiation protocol between our system agents. The proposed ontology mapping negotiation model based on the knowledge management system for supporting the semantic heterogeneity and it organized as follow: Negotiation Layer (NL), the Semantic Layer (SEL), and the Knowledge Management Systems Layer(KMSL).We detailed also the reassignment process by using Dynamic Reassigned Tasks (DRT) algorithm supporting by ontology mapping approach. Finally, the experimental results presented in this thesis, justify the using of the ontology solution in our system and its role in the negotiation process

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Mahdoui, Chedly Nesrine. "Communicating multi-UAV system for cooperative SLAM-based exploration." Thesis, Compiègne, 2018. http://www.theses.fr/2018COMP2447/document.

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Dans la communauté robotique aérienne, un croissant intérêt pour les systèmes multirobot (SMR) est apparu ces dernières années. Cela a été motivé par i) les progrès technologiques, tels que de meilleures capacités de traitement à bord des robots et des performances de communication plus élevées, et ii) les résultats prometteurs du déploiement de SMR tels que l’augmentation de la zone de couverture en un minimum de temps. Le développement d’une flotte de véhicules aériens sans pilote (UAV: Unmanned Aerial Vehicle) et de véhicules aériens de petite taille (MAV: Micro Aerial Vehicle) a ouvert la voie à de nouvelles applications à grande échelle nécessitant les caractéristiques de tel système de systèmes dans des domaines tels que la sécurité, la surveillance des catastrophes et des inondations, la recherche et le sauvetage, l’inspection des infrastructures, et ainsi de suite. De telles applications nécessitent que les robots identifient leur environnement et se localisent. Ces tâches fondamentales peuvent être assurées par la mission d’exploration. Dans ce contexte, cette thèse aborde l’exploration coopérative d’un environnement inconnu en utilisant une équipe de drones avec vision intégrée. Nous avons proposé un système multi-robot où le but est de choisir des régions spécifiques de l’environnement à explorer et à cartographier simultanément par chaque robot de manière optimisée, afin de réduire le temps d’exploration et, par conséquent, la consommation d’énergie. Chaque UAV est capable d’effectuer une localisation et une cartographie simultanées (SLAM: Simultaneous Localization And Mapping) à l’aide d’un capteur visuel comme principale modalité de perception. Pour explorer les régions inconnues, les cibles – choisies parmi les points frontières situés entre les zones libres et les zones inconnues – sont assignées aux robots en considérant un compromis entre l’exploration rapide et l’obtention d’une carte détaillée. À des fins de prise de décision, les UAVs échangent habituellement une copie de leur carte locale, mais la nouveauté dans ce travail est d’échanger les points frontières de cette carte, ce qui permet d’économiser la bande passante de communication. L’un des points les plus difficiles du SMR est la communication inter-robot. Nous étudions cette partie sous les aspects topologiques et typologiques. Nous proposons également des stratégies pour faire face à l’abandon ou à l’échec de la communication. Des validations basées sur des simulations étendues et des bancs d’essai sont présentées<br>In the aerial robotic community, a growing interest for Multi-Robot Systems (MRS) appeared in the last years. This is thanks to i) the technological advances, such as better onboard processing capabilities and higher communication performances, and ii) the promising results of MRS deployment, such as increased area coverage in minimum time. The development of highly efficient and affordable fleet of Unmanned Aerial Vehicles (UAVs) and Micro Aerial Vehicles (MAVs) of small size has paved the way to new large-scale applications, that demand such System of Systems (SoS) features in areas like security, disaster surveillance, inundation monitoring, search and rescue, infrastructure inspection, and so on. Such applications require the robots to identify their environment and localize themselves. These fundamental tasks can be ensured by the exploration mission. In this context, this thesis addresses the cooperative exploration of an unknown environment sensed by a team of UAVs with embedded vision. We propose a multi-robot framework where the key problem is to cooperatively choose specific regions of the environment to be simultaneously explored and mapped by each robot in an optimized manner in order to reduce exploration time and, consequently, energy consumption. Each UAV is able to performSimultaneous Localization And Mapping (SLAM) with a visual sensor as the main input sensor. To explore the unknown regions, the targets – selected from the computed frontier points lying between free and unknown areas – are assigned to robots by considering a trade-off between fast exploration and getting detailed grid maps. For the sake of decision making, UAVs usually exchange a copy of their local map; however, the novelty in this work is to exchange map frontier points instead, which allow to save communication bandwidth. One of the most challenging points in MRS is the inter-robot communication. We study this part in both topological and typological aspects. We also propose some strategies to cope with communication drop-out or failure. Validations based on extensive simulations and testbeds are presented

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Su-WeiLin and 林舒葦. "Accuracy Improvement of Terrestrial Mobile Mapping Systems Using Triangulation Adjustment." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/s6nu5v.

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碩士<br>國立成功大學<br>測量及空間資訊學系<br>105<br>Traditionally, aerial Photogrammetry is used to do large area measurements by aerial images. However, taking images from an airplane can be so easily affected by weather that the time limitation related to taking images is very serious, and aerial Photogrammetry is also expensive. The other problem by Photogrammetry is the lack of façades of houses. Therefore, to overcome these problems, Mobile Mapping Systems (MMS) have been developed. In this article, a terrestrial MMS is used for the research. If a terrestrial MMS combines GPSs and an IMU, it can perform direct geo-referencing and then a forward intersection to determine many ground coordinates of points. However, the accuracy of results using terrestrial MMS is not stable or reliable, and thus this approach may be worse than using aerial Photogrammetry. This research introduces exterior orientation obtained from a terrestrial MMS with the help of ground control points introduced into bundle block adjustment in order to improve the positioning accuracy. The positioning accuracy will be significantly improved when we set a pair of ground control points every 60m. Using an exterior orientation from a terrestrial MMS with a pair of ground control points placed every 60m and using bundle block adjustment can raise the accuracy from 2232cm to 15cm.

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(6843914), Radhika Ravi. "Interactive Environment For The Calibration And Visualization Of Multi-sensor Mobile Mapping Systems." Thesis, 2019.

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<div>LiDAR units onboard airborne and terrestrial platforms have been established as a proven technology for the acquisition of dense point clouds for a wide range of applications, such as digital building model generation, transportation corridor monitoring, precision agriculture, and infrastructure monitoring. Furthermore, integrating such systems with one or more cameras would allow forward and backward projection between imagery and LiDAR data, thus facilitating several high-level data processing activities such as reliable feature extraction and colorization of point clouds. However, the attainment of the full 3D point positioning potential of such systems is contingent on an accurate calibration of the mobile mapping unit as a whole. </div><div> </div><div> This research aims at proposing a calibration procedure for terrestrial multi-unit LiDAR systems to directly estimate the mounting parameters relating several spinning multi-beam laser scanners to the onboard GNSS/INS unit in order to derive point clouds with high positional accuracy. To ensure the accuracy of the estimated mounting parameters, an optimal configuration of target primitives and drive-runs is determined by analyzing the potential impact of bias in mounting parameters of a LiDAR unit on the resultant point cloud for different orientations of target primitives and different drive-run scenarios. This impact is also verified experimentally by simulating a bias in each mounting parameter separately. Next, the optimal configuration is used within an experimental setup to evaluate the performance of the proposed calibration procedure. Then, this proposed multi-unit LiDAR system calibration strategy is extended for multi-LiDAR multi-camera systems in order to allow a simultaneous estimation of the mounting parameters relating the different laser scanners as well as cameras to the onboard GNSS/INS unit. Such a calibration improves the registration accuracy of point clouds derived from LiDAR data and imagery, along with their accuracy with respect to the ground truth. Finally, in order to qualitatively evaluate the calibration results for a generic mobile mapping system and allow the visualization of point clouds, imagery data, and their registration quality, an interface denoted as Image-LiDAR Interactive Visualization Environment (I-LIVE) is developed. Apart from its visualization functions (such as 3D point cloud manipulation and image display/navigation), I-LIVE mainly serves as a tool for the quality control of GNSS/INS-derived trajectory and LiDAR-camera system calibration. </div><div> </div><div> The proposed multi-sensor system calibration procedures are experimentally evaluated by calibrating several mobile mapping platforms with varying number of LiDAR units and cameras. For all cases, the system calibration is seen to attain accuracies better than the ones expected based on the specifications of the involved hardware components, i.e., the LiDAR units, cameras, and GNSS/INS units.</div>

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Ta-TzuTsai and 蔡大慈. "Linear solution algorithm for overdetermined seven-parameter transformation positioning problems by Mobile Mapping Systems." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/4mdr6y.

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Wang, Carlos. "Monocular Vision-Based Obstacle Detection for Unmanned Systems." Thesis, 2011. http://hdl.handle.net/10012/5890.

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Many potential indoor applications exist for autonomous vehicles, such as automated surveillance, inspection, and document delivery. A key requirement for autonomous operation is for the vehicles to be able to detect and map obstacles in order to avoid collisions. This work develops a comprehensive 3D scene reconstruction algorithm based on known vehicle motion and vision data that is specifically tailored to the indoor environment. Visible light cameras are one of the many sensors available for capturing information from the environment, and their key advantages over other sensors are that they are light weight, power efficient, cost effective, and provide abundant information about the scene. The emphasis on 3D indoor mapping enables the assumption that a large majority of the area to be mapped is comprised of planar surfaces such as floors, walls and ceilings, which can be exploited to simplify the complex task of dense reconstruction of the environment from monocular vision data. In this thesis, the Planar Surface Reconstruction (PSR) algorithm is presented. It extracts surface information from images and combines it with 3D point estimates in order to generate a reliable and complete environment map. It was designed to be used for single cameras with the primary assumptions that the objects in the environment are flat, static and chromatically unique. The algorithm finds and tracks Scale Invariant Feature Transform (SIFT) features from a sequence of images to calculate 3D point estimates. The individual surface information is extracted using a combination of the Kuwahara filter and mean shift segmentation, which is then coupled with the 3D point estimates to fit these surfaces in the environment map. The resultant map consists of both surfaces and points that are assumed to represent obstacles in the scene. A ground vehicle platform was developed for the real-time implementation of the algorithm and experiments were done to assess the PSR algorithm. Both clean and cluttered scenarios were used to evaluate the quality of the surfaces generated from the algorithm. The clean scenario satisfies the primary assumptions underlying the PSR algorithm, and as a result produced accurate surface details of the scene, while the cluttered scenario generated lower quality, but still promising, results. The significance behind these findings is that it is shown that incorporating object surface recognition into dense 3D reconstruction can significantly improve the overall quality of the environment map.

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Lockyer-Cotter, James. "Web GIS Tools for Crime Mapping in Toronto." Thesis, 2013. http://hdl.handle.net/10012/7900.

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The field of crime mapping has an extensive history, yet it has managed to remain an effective tool for policing even in modern times. This success can be attributed in part to the field’s willingness to adapt to newer technologies as they have become available. A current trend that is occurring internationally is the practice of online crime mapping. Many police services from around the world have recognized the importance of using the Internet to connect with the public that they serve. To this end, while most police services have an online presence in the form of a Web site, some have opted to go further and to publish their crime data spatially in the form of an interactive Web-based mapping application. Presently, the City of Toronto has opted not to engage in interactive Web mapping and has limited their online publications to only static maps and written crime reports. This thesis attempts to build upon the capabilities that are offered by Web GIS tools for crime mapping applications in the City of Toronto. To achieve this, two Web applications were developed to help facilitate the process of reporting crime incidents and gang-related graffiti. The services in these Web applications were developed using ArcGIS for Desktop 10.1 and hosted using ArcGIS for Server 10.1, while the Web applications themselves were developed using the ArcGIS API for JavaScript. Each application was designed to support interactive incident mapping, as well as anonymous incident reporting. In addition, the Graffiti Tagger application utilized a mobile-themed interface and image attachments to promote on-the-go graffiti incident reporting. By doing this, it was hypothesized that the overall quality and quantity of data contributed to the Toronto Police Service would increase. To test this hypothesis, a survey was developed and released to a number of participants with varying backgrounds and technical skill levels. The results of this survey showed that a public desire did exist for both of these Web applications, along with a willingness from the majority of participants to voluntarily participate in using these applications. These results suggest that adopting the use of Web mapping applications has the potential to increase the quantity, and potentially the quality, of crime data that is reported.

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DuongThanhTrung and 楊成中. "INTEGRATION STRATEGIES AND ESTIMATION ALGORITHMS TO IMPROVE THE NAVIGATION ACCURACY OF LAND-BASED MOBILE MAPPING SYSTEMS." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/w2729k.

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博士<br>國立成功大學<br>測量及空間資訊學系<br>102<br>Mobile mapping systems (MMSs) have been widely used to rapidly acquire spatial information. In such a system, the integration of the Inertial Navigation System (INS) and the Global Positioning System (GPS) is popularly applied as a direct geo-referencing system to seamlessly determine the time-variable position and orientation parameters. Given that both INS and GPS are affected by various error sources, these errors deteriorate the overall position and orientation accuracy of an integrated system that uses conventional INS/GPS integration strategies. These strategies include loosely coupled and common estimation strategies such as Kalman filter. These errors particularly occur when using low cost, small size inertial sensors and GPS receivers, or operating in GPS-hostile environments such as in urban canyons. The use of expensive equipment can improve the performance of the system, but also increases its overall cost. In some operating conditions, the high cost devices still do not fulfill the user’s requirements with the current dada fusion techniques. This study aims to improve the navigation solution accuracy of a land-based MMS utilizing a low cost inertial sensor and GPS receiver by focusing on integration strategies and advanced estimation algorithms. For INS/GPS integration, a modified tightly coupled scheme was proposed to overcome the limitations of current tightly coupled and loosely coupled schemes. Various additional aids and constrains are discussed and applied to improve the robustness of the system in cases of GPS signal outages. For the estimation strategies, the efficiency of different filtering techniques such as KF, Unscented KF, particle filter, and hybrid filtering are analyzed using simulation and real data. A new estimation method called on-line smoothing is proposed to overcome the problems of filtering techniques and conventional smoothing algorithms. Various field tests using different devices and testing scenarios were conducted to evaluate the proposed methods. The analyzed results indicate that the proposed strategies and algorithms can significantly improve the performance of the system compared with conventional schemes. In various testing scenarios, the improvement of the modified TC over pure LC is about 60% and in GPS-denied environment, with the aid of additional constrains, the improvement of proposed scheme can reach to 90% over the scheme with INS/GPS.

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Dissertations / Theses on the topic 'Mobile mapping systems'

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