Pub Date : 2010-12-03DOI: 10.1109/UPINLBS.2010.5653830
P. Davidson, J. Collin, J. Takala
This paper presents a numerical approach to the pedestrian map-matching problem using building plans. The proposed solution is based on a sequential Monte Carlo method, so called particle filtering. This algorithm can be adapted for implementation on real-time pedestrian navigation systems using low-cost MEMS gyroscopes and accelerometers as dead-reckoning sensors. The algorithm reliability and accuracy performance was investigated using simulated data typical for pedestrians walking inside building. The results show that this map-aided dead reckoning system is able to provide accurate indoor positioning for long periods of time without using GPS data.
{"title":"Application of particle filters for indoor positioning using floor plans","authors":"P. Davidson, J. Collin, J. Takala","doi":"10.1109/UPINLBS.2010.5653830","DOIUrl":"https://doi.org/10.1109/UPINLBS.2010.5653830","url":null,"abstract":"This paper presents a numerical approach to the pedestrian map-matching problem using building plans. The proposed solution is based on a sequential Monte Carlo method, so called particle filtering. This algorithm can be adapted for implementation on real-time pedestrian navigation systems using low-cost MEMS gyroscopes and accelerometers as dead-reckoning sensors. The algorithm reliability and accuracy performance was investigated using simulated data typical for pedestrians walking inside building. The results show that this map-aided dead reckoning system is able to provide accurate indoor positioning for long periods of time without using GPS data.","PeriodicalId":373653,"journal":{"name":"2010 Ubiquitous Positioning Indoor Navigation and Location Based Service","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132725872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-03DOI: 10.1109/UPINLBS.2010.5653563
Joni Jämsä, Mika Luimula, S. Pieskä, Veikko Brax, Ossi Saukko, P. Verronen
In the current paper, we describe a three dimensional indoor positioning system for the metal industry. The developed system consists of a three dimensional map-based user interface scanned with Leica ScanStation 2, Chirp Spread Spectrum modulation (CSS) indoor positioning technology, and a used positioning algorithm. The system development process described in this paper includes three phases. Firstly, the modelling of three dimensional virtual environments with an accuracy of 2 centimeters required the use of point cloud processing software and 3D content creation. The next phase was to find reliable indoor positioning technology for harsh industrial conditions. The results reported in this paper show that a reliable positioning system using CSS could be created. Finally, location information provided by CSS was shown in the three dimensional map-based user interface. The user interface was based on CENTRIA's Locawe platform. The process described in this paper shows that moving objects such as mobile robots, autonomous transporters or working machines can be tracked in a three dimensional virtual environment.
{"title":"Indoor positioning with laser scanned models in the metal industry","authors":"Joni Jämsä, Mika Luimula, S. Pieskä, Veikko Brax, Ossi Saukko, P. Verronen","doi":"10.1109/UPINLBS.2010.5653563","DOIUrl":"https://doi.org/10.1109/UPINLBS.2010.5653563","url":null,"abstract":"In the current paper, we describe a three dimensional indoor positioning system for the metal industry. The developed system consists of a three dimensional map-based user interface scanned with Leica ScanStation 2, Chirp Spread Spectrum modulation (CSS) indoor positioning technology, and a used positioning algorithm. The system development process described in this paper includes three phases. Firstly, the modelling of three dimensional virtual environments with an accuracy of 2 centimeters required the use of point cloud processing software and 3D content creation. The next phase was to find reliable indoor positioning technology for harsh industrial conditions. The results reported in this paper show that a reliable positioning system using CSS could be created. Finally, location information provided by CSS was shown in the three dimensional map-based user interface. The user interface was based on CENTRIA's Locawe platform. The process described in this paper shows that moving objects such as mobile robots, autonomous transporters or working machines can be tracked in a three dimensional virtual environment.","PeriodicalId":373653,"journal":{"name":"2010 Ubiquitous Positioning Indoor Navigation and Location Based Service","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116310558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-03DOI: 10.1109/UPINLBS.2010.5654340
L. Patino-Studencki, U. Batzer, J. Thielecke
A derivation of phase smoothing for a pseudolite system is given. The distinction to phase smoothing known from literature arises from the setup of the system. As of the employed free-running pseudolites, the main challenge is to properly estimate the pseudolite clocks. The better the pseudolite clocks are estimated, the more precise are the phase measurements and the more effective is phase smoothing. Two different methods for clock estimation are examined in terms of their applicability to phase smoothing. Simulated as well as real data are used in order to evaluate the precision gain by phase smoothing. Optimal solutions according to system restrictions are presented.
{"title":"Phase smoothing in a virtually synchronized pseudolite system using stochastic clock modelling","authors":"L. Patino-Studencki, U. Batzer, J. Thielecke","doi":"10.1109/UPINLBS.2010.5654340","DOIUrl":"https://doi.org/10.1109/UPINLBS.2010.5654340","url":null,"abstract":"A derivation of phase smoothing for a pseudolite system is given. The distinction to phase smoothing known from literature arises from the setup of the system. As of the employed free-running pseudolites, the main challenge is to properly estimate the pseudolite clocks. The better the pseudolite clocks are estimated, the more precise are the phase measurements and the more effective is phase smoothing. Two different methods for clock estimation are examined in terms of their applicability to phase smoothing. Simulated as well as real data are used in order to evaluate the precision gain by phase smoothing. Optimal solutions according to system restrictions are presented.","PeriodicalId":373653,"journal":{"name":"2010 Ubiquitous Positioning Indoor Navigation and Location Based Service","volume":"150 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116387096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-03DOI: 10.1109/UPINLBS.2010.5654028
Christoph Settgast, M. Klepal, M. Weyn
In a complex tracking environment like an airport many objects are tracked simultaneously. Some of these objects correlate to each other naturally, and thus the questions are how this correlation can be detected and how it can be used for increasing accuracy of the localisation system. The detection of the correlation is done by deciding if two objects are physically or logically bound or connected with each other. This could for example imply that a person is carrying a suitcase or sitting in a car, if these objects are tracked in a localisation system. The proposed approach to answer this question follows a two-step approach by checking computational-inexpensive preconditions first and evaluating a test statistic afterwards. This test statistic must be independent on the used fusion filter like Kalman or Particle Filter. Our results show, that one can reliably detect the physical binding and unbinding events and furthermore increase the location accuracy.
{"title":"Object correlation evaluation for location data fusion","authors":"Christoph Settgast, M. Klepal, M. Weyn","doi":"10.1109/UPINLBS.2010.5654028","DOIUrl":"https://doi.org/10.1109/UPINLBS.2010.5654028","url":null,"abstract":"In a complex tracking environment like an airport many objects are tracked simultaneously. Some of these objects correlate to each other naturally, and thus the questions are how this correlation can be detected and how it can be used for increasing accuracy of the localisation system. The detection of the correlation is done by deciding if two objects are physically or logically bound or connected with each other. This could for example imply that a person is carrying a suitcase or sitting in a car, if these objects are tracked in a localisation system. The proposed approach to answer this question follows a two-step approach by checking computational-inexpensive preconditions first and evaluating a test statistic afterwards. This test statistic must be independent on the used fusion filter like Kalman or Particle Filter. Our results show, that one can reliably detect the physical binding and unbinding events and furthermore increase the location accuracy.","PeriodicalId":373653,"journal":{"name":"2010 Ubiquitous Positioning Indoor Navigation and Location Based Service","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132164514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-03DOI: 10.1109/UPINLBS.2010.5654106
Nathan Knight, A. Almagbile, Jinling Wang, W. Ding, Yiping Jiang
Reliability and integrity has become increasingly important in ubiquitous positioning systems, and particularly in critical applications. To implement reliability and integrity measures, Fault Detection and Exclusion (FDE) procedures should be used. However, the current FDE procedures in the chi-square test and the outlier test are suboptimal in terms of continuity and availability. This is due to the assumption that the bias always corresponds with the measurement that has the largest Protection Level (PL), and in the setting of the continuity probability to a predefined value rather than being maximised.
{"title":"Optimising Fault Detection and Exclusion in positioning","authors":"Nathan Knight, A. Almagbile, Jinling Wang, W. Ding, Yiping Jiang","doi":"10.1109/UPINLBS.2010.5654106","DOIUrl":"https://doi.org/10.1109/UPINLBS.2010.5654106","url":null,"abstract":"Reliability and integrity has become increasingly important in ubiquitous positioning systems, and particularly in critical applications. To implement reliability and integrity measures, Fault Detection and Exclusion (FDE) procedures should be used. However, the current FDE procedures in the chi-square test and the outlier test are suboptimal in terms of continuity and availability. This is due to the assumption that the bias always corresponds with the measurement that has the largest Protection Level (PL), and in the setting of the continuity probability to a predefined value rather than being maximised.","PeriodicalId":373653,"journal":{"name":"2010 Ubiquitous Positioning Indoor Navigation and Location Based Service","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128510969","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-03DOI: 10.1109/UPINLBS.2010.5654324
Chen Liang, Henri Pesonen, R. Piché
This paper studies the mobile tracking problem in mixed line-of-sight (LOS) and non-line-of-sight (NLOS) conditions, where the statistics of NLOS error are assumed unknown. Three different models are used to describe the NLOS errors. A Rao-Blackwellized particle filtering with parameter learning (RBPF-PL) is presented, in which the posterior of sight conditions is estimated by particle filtering while the mobile state and NLOS parameters are analytically computed. Simulation results are provided to evaluate the performance of RBPF-PL variants in different situations. Simulation show that unless it is known that NLOS noise has the same bias and variance in all the observations, the more complicated models should be employed as they work correctly even in NLOS model mismatch, with only slightly more computational complexity.
{"title":"Mobile tracking in unknown non-line-of-sight conditions","authors":"Chen Liang, Henri Pesonen, R. Piché","doi":"10.1109/UPINLBS.2010.5654324","DOIUrl":"https://doi.org/10.1109/UPINLBS.2010.5654324","url":null,"abstract":"This paper studies the mobile tracking problem in mixed line-of-sight (LOS) and non-line-of-sight (NLOS) conditions, where the statistics of NLOS error are assumed unknown. Three different models are used to describe the NLOS errors. A Rao-Blackwellized particle filtering with parameter learning (RBPF-PL) is presented, in which the posterior of sight conditions is estimated by particle filtering while the mobile state and NLOS parameters are analytically computed. Simulation results are provided to evaluate the performance of RBPF-PL variants in different situations. Simulation show that unless it is known that NLOS noise has the same bias and variance in all the observations, the more complicated models should be employed as they work correctly even in NLOS model mismatch, with only slightly more computational complexity.","PeriodicalId":373653,"journal":{"name":"2010 Ubiquitous Positioning Indoor Navigation and Location Based Service","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132899606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-03DOI: 10.1109/UPINLBS.2010.5654049
Kavitha Muthukrishnan, S. Dulman, K. Langendoen
Providing ad-hoc solutions for positioning and tracking of emergency response teams is an important and safety-critical challenge. Although solutions based on inertial sensing systems are promising, they are subject to drift. We address the problem of positional drift by having the responders themselves deploy beacons, specifically ultrasound beacons, as they progress into an unknown environment. Our research focuses on a sensor network approach that does not require any pre-deployment of infrastructure. This paper targets two important aspects within the context of providing positioning service for emergency responders namely on how to locate the deployed static beacons, and on how to track the responders by using a combination of ultrasound and inertial measurements. The main contributions of this paper are: (i) characterisation of the errors encountered in an inertial-based pedestrian dead reckoning solution and ultrasound range measurements in a mobile setting, (ii) an algorithm for ultrasound beacon localisation (using multidimensional scaling), (iii) formulation of a Kalman filtering based algorithm for tracking the responder using a combination of ultrasound range and inertial measurements, and (iv) the presented algorithms are evaluated using data collected from real deployments and are compared against an ultra-wideband (UWB) precision location system. Our approach of preventing the drift in inertial estimates by combining with ultrasound measurements are promising and offers a viable solution to providing positioning and tracking support to emergency responders.
{"title":"Towards a rapidly deployable positioning system for emergency responders","authors":"Kavitha Muthukrishnan, S. Dulman, K. Langendoen","doi":"10.1109/UPINLBS.2010.5654049","DOIUrl":"https://doi.org/10.1109/UPINLBS.2010.5654049","url":null,"abstract":"Providing ad-hoc solutions for positioning and tracking of emergency response teams is an important and safety-critical challenge. Although solutions based on inertial sensing systems are promising, they are subject to drift. We address the problem of positional drift by having the responders themselves deploy beacons, specifically ultrasound beacons, as they progress into an unknown environment. Our research focuses on a sensor network approach that does not require any pre-deployment of infrastructure. This paper targets two important aspects within the context of providing positioning service for emergency responders namely on how to locate the deployed static beacons, and on how to track the responders by using a combination of ultrasound and inertial measurements. The main contributions of this paper are: (i) characterisation of the errors encountered in an inertial-based pedestrian dead reckoning solution and ultrasound range measurements in a mobile setting, (ii) an algorithm for ultrasound beacon localisation (using multidimensional scaling), (iii) formulation of a Kalman filtering based algorithm for tracking the responder using a combination of ultrasound range and inertial measurements, and (iv) the presented algorithms are evaluated using data collected from real deployments and are compared against an ultra-wideband (UWB) precision location system. Our approach of preventing the drift in inertial estimates by combining with ultrasound measurements are promising and offers a viable solution to providing positioning and tracking support to emergency responders.","PeriodicalId":373653,"journal":{"name":"2010 Ubiquitous Positioning Indoor Navigation and Location Based Service","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122123476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-03DOI: 10.1109/UPINLBS.2010.5654337
T. Paakki, J. Raasakka, F. D. Rosa, H. Hurskainen, J. Nurmi
Recently a lot of research has been going on in the field of Global Navigation Satellite System receivers. Only few projects have been providing open source hardware receivers. In this paper we present a university based GNSS receiver intended for open source release. The highly modular design of the receiver is described in detail. We also provide description of the software parts and advanced user interface of the receiver. In the end of the paper a test scenario is provided proving the functionality of the receiver design. The presented GNSS receiver architecture is expected to be valuable prototype for research purposes.
{"title":"TUTGNSS University based hardware/software GNSS receiver for research purposes","authors":"T. Paakki, J. Raasakka, F. D. Rosa, H. Hurskainen, J. Nurmi","doi":"10.1109/UPINLBS.2010.5654337","DOIUrl":"https://doi.org/10.1109/UPINLBS.2010.5654337","url":null,"abstract":"Recently a lot of research has been going on in the field of Global Navigation Satellite System receivers. Only few projects have been providing open source hardware receivers. In this paper we present a university based GNSS receiver intended for open source release. The highly modular design of the receiver is described in detail. We also provide description of the software parts and advanced user interface of the receiver. In the end of the paper a test scenario is provided proving the functionality of the receiver design. The presented GNSS receiver architecture is expected to be valuable prototype for research purposes.","PeriodicalId":373653,"journal":{"name":"2010 Ubiquitous Positioning Indoor Navigation and Location Based Service","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115763572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-03DOI: 10.1109/UPINLBS.2010.5653558
Lingli Zhu, J. Hyyppä, Ruizhi Chen, Zhengjun Liu
Nowadays 3D concepts are tightly related to our lives. However one of the challenges for 3D applications is the huge amount of datasets. Therefore data reduction is critical for the increasing applications, especially for limited memory and storage space devices, e.g. mobile phone. In this paper, we propose an approach of 3D model simplification for mobile phone based navigation application. This method is developed based on the data from 3D models of Finnish pavilion. Our objectives are to reduce the model to the reasonable size and keep original appearance and realize the localization of data storage for the display, rendering and navigating on mobile phone. We use 2D projections of 3D data and line sweeping methods to extract the key points of models and data reduce to almost 4 percent of the original data. As a result, the indoor models of Finnish pavilion are successfully shown and apply for indoor navigation.
{"title":"An approach of 3D model simplification for mobile phone based navigation application","authors":"Lingli Zhu, J. Hyyppä, Ruizhi Chen, Zhengjun Liu","doi":"10.1109/UPINLBS.2010.5653558","DOIUrl":"https://doi.org/10.1109/UPINLBS.2010.5653558","url":null,"abstract":"Nowadays 3D concepts are tightly related to our lives. However one of the challenges for 3D applications is the huge amount of datasets. Therefore data reduction is critical for the increasing applications, especially for limited memory and storage space devices, e.g. mobile phone. In this paper, we propose an approach of 3D model simplification for mobile phone based navigation application. This method is developed based on the data from 3D models of Finnish pavilion. Our objectives are to reduce the model to the reasonable size and keep original appearance and realize the localization of data storage for the display, rendering and navigating on mobile phone. We use 2D projections of 3D data and line sweeping methods to extract the key points of models and data reduce to almost 4 percent of the original data. As a result, the indoor models of Finnish pavilion are successfully shown and apply for indoor navigation.","PeriodicalId":373653,"journal":{"name":"2010 Ubiquitous Positioning Indoor Navigation and Location Based Service","volume":"89 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126202311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-03DOI: 10.1109/UPINLBS.2010.5653939
Kostas Dragunas, K. Borre
There are many applications that require continuous positioning in combined outdoor urban and indoor environments. GNSS has been used for a long time in outdoor environments, while indoor positioning is still a challenging task. One of the major degradations that GNSS receivers experience indoors is the presence of multipath. The current paper analyzes several available multipath mitigation techniques which would be suitable for indoor applications. A few deconvolution based techniques such as the Projection Onto Convex Sets and the Deconvolution Approach are selected for closer investigation and their performance is demonstrated by using a controlled environment setup.
{"title":"Indoor multipath mitigation","authors":"Kostas Dragunas, K. Borre","doi":"10.1109/UPINLBS.2010.5653939","DOIUrl":"https://doi.org/10.1109/UPINLBS.2010.5653939","url":null,"abstract":"There are many applications that require continuous positioning in combined outdoor urban and indoor environments. GNSS has been used for a long time in outdoor environments, while indoor positioning is still a challenging task. One of the major degradations that GNSS receivers experience indoors is the presence of multipath. The current paper analyzes several available multipath mitigation techniques which would be suitable for indoor applications. A few deconvolution based techniques such as the Projection Onto Convex Sets and the Deconvolution Approach are selected for closer investigation and their performance is demonstrated by using a controlled environment setup.","PeriodicalId":373653,"journal":{"name":"2010 Ubiquitous Positioning Indoor Navigation and Location Based Service","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124779031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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