Location Fingerprint Extraction for Magnetic Field Magnitude Based Indoor Positioning

Smartphone based indoor positioning has greatly helped people in finding their positions in complex and unfamiliar buildings. One popular positioning method is by utilizing indoor magnetic field, because this feature is stable and infrastructure-free. In this method, the magnetometer embedded on the smartphone measures indoor magnetic field and queries its position. However, the environments of the magnetometer are rather harsh. This harshness mainly consists of coarse-grained hard/soft-iron calibrations and sensor electronic noise. The two kinds of interferences decrease the position distinguishability of the magnetic field. Therefore, it is important to extract location features from magnetic fields to reduce these interferences. This paper analyzes the main interference sources of the magnetometer embedded on the smartphone. In addition, we present a feature distinguishability measurement technique to evaluate the performance of different feature extraction methods. Experiments revealed that selected fingerprints will improve position distinguishability

Embeddable Advanced Sensors for Harsh Environment Sensing Applications

Research and development in advanced sensors with embedded monitoring capability have experienced significant growth in recent years, fueled by their broad applications in real-time measurement of a wide variety of physical, chemical, and biological quantities. Compared with conventional sensors with bulky assemblies, recent progress in 3D manufacturing technologies (e.g., ultrafast laser micromachining and additive manufacturing) has opened up a new avenue in one-step fabrication of assembly-freemicro devices in various materials as well as the development of compact, customized, and intricate smart structures/components. The merits of these advanced manufacturing techniques enable the integration of embeddable advanced sensors into smart structures and components for improved robustness, enriched functionality, enhanced intelligence, and unprecedented performance

Estimation of Indoor Location Through Magnetic Field Data: An Approach Based On Convolutional Neural Networks

Estimation of indoor location represents an interesting research topic since it is a main contextual variable for location bases services (LBS), eHealth applications and commercial systems, among others. For instance, hospitals require location data of their employees, as well as the location of their patients to offer services based on these locations at the correct moments of their needs. Several approaches have been proposed to tackle this problem using different types of artificial or natural signals (ie, wifi, bluetooth, rfid, sound, movement, etc.). In this work, it is proposed the development of an indoor location estimator system, relying in the data provided by the magnetic field of the rooms, which has been demonstrated that is unique and quasi-stationary. For this purpose, it is analyzed the spectral evolution of the magnetic field data viewed as a bidimensional heatmap, avoiding temporal dependencies. A Fourier transform is applied to the bidimensional heatmap of the magnetic field data to feed a convolutional neural network (CNN) to generate a model to estimate the user’s location in a building. The evaluation of the CNN model to deploy an indoor location system (ILS) is done through measuring the Receiver Operating Characteristic (ROC) curve to observe the behavior in terms of sensitivity and specificity. Our experiments achieve a 0.99 Area Under the Curve (AUC) in the training data-set and a 0.74 in a total blind data set.Estimation of indoor location represents an interesting research topic since it is a main contextual variable for location bases services (LBS), eHealth applications and commercial systems, among others. For instance, hospitals require location data of their employees, as well as the location of their patients to offer services based on these locations at the correct moments of their needs. Several approaches have been proposed to tackle this problem using different types of artificial or natural signals (ie, wifi, bluetooth, rfid, sound, movement, etc.). In this work, it is proposed the development of an indoor location estimator system, relying in the data provided by the magnetic field of the rooms, which has been demonstrated that is unique and quasi-stationary. For this purpose, it is analyzed the spectral evolution of the magnetic field data viewed as a bidimensional heatmap, avoiding temporal dependencies. A Fourier transform is applied to the bidimensional heatmap of the magnetic field data to feed a convolutional neural network (CNN) to generate a model to estimate the user’s location in a building. The evaluation of the CNN model to deploy an indoor location system (ILS) is done through measuring the Receiver Operating Characteristic (ROC) curve to observe the behavior in terms of sensitivity and specificity. Our experiments achieve a 0.99 Area Under the Curve (AUC) in the training data-set and a 0.74 in a total blind data set

Design of a mobile augmented reality-based indoor navigation system

GPS-based navigation technology has been widely used in most of the commercial navigation applications nowadays. However, its usage in indoor navigation is not as effective as when it is used at outdoor environment. Much research and developments of indoor navigation technology involve additional hardware installation which usually incur high setup cost. In this paper, research and comparisons were done to determine the appropriate techniques of indoor positioning, pathfinding, and route guidance for an indoor navigation method. The aim of this project is to present a simple and cost effective indoor navigation system. The proposed system uses the existing built-in sensors embedded in most of the mobile devices to detect the user location, integrates with AR technology to provide user an immersive navigation experience. In this project, an indoor navigation mobile application was developed and tested. The development demonstrates the usage of Indoor Atlas which enables indoor positioning through technology fusion to detect user’s position and obtain the route to destination, and AR Core to display AR guidance using the computed route. Surveys were carried out to gauge the efficiency of the method and to gather the feedback from the participants. The architecture of the method and the demonstration of the application is presented

ANALIZA SUSTAVA ZA UNUTARNJE LOCIRANJE

Recently, due to advances in the development of various technologies which can be used for locating, it is possible to develop systems which include software solutions for the user locationing and guidance in the interior, closed or covered areas where the existing location technologies and systems for locating and guidance applicable at open, outdoor areas cannot be used. This paper analyses the available hardware, software and network technologies which can be used for creating a positioning system for interior, closed or covered area. The paper analyses technologies which can be used in such distributed systems for the implementation of functionalities that are needed or required in the Indoor Positioning System (IPS). The paper describes the concept of the IPS system. It presents the IPS systems available on the market. It shows the technologies that can be used to implement the IPS system and the analyses of categories which affect the IPS system implementation. The paper demonstrates that none of the technologies analysed meet all of the observed categories while the BLE technology achieves the most favourable results in individual categories.Zbog napretka u razvoju raznih tehnologija koje se mogu koristiti za lociranje, u posljednje vrijeme razvijaju se sustavi koji uključuju programska rješenja za lociranje i navođenje korisnika u unutarnjem, zatvorenom ili natkrivenom prostoru, gdje se postojeće tehnologije za lociranje i sustavi za lociranje i navođenje koje se primjenjuju kod otvorenih, vanjskih prostora, ne mogu koristiti. U radu se analiziraju dostupne hardverske, softverske i mrežne tehnologije kojima je moguće izraditi sustav za unutarnje lociranje, odnosno tehnologije kojima takav distribuirani sustav po svom karakteru i implementiranim funkcijama postaje sustav za lociranje u zatvorenom prostoru (IPS, engl. Indoor Positioning System). Opisan je koncept IPS sustava. Prikazani su gotovi IPS sustavi dostupni na tržištu. Pokazane su tehnologije koje se mogu koristiti za implementaciju IPS-a i izrađena analiza kategorija koje utječu na implementaciju IPS-a. Pokazano je da niti jedna tehnologija ne zadovoljava sve promatrane kategorije, no BLE tehnologija omogućuje ostvarenje najpovoljnijih rezultata po pojedinim kategorijama

ANALIZA SUSTAVA ZA UNUTARNJE LOCIRANJE

Recently, due to advances in the development of various technologies which can be used for locating, it is possible to develop systems which include software solutions for the user locationing and guidance in the interior, closed or covered areas where the existing location technologies and systems for locating and guidance applicable at open, outdoor areas cannot be used. This paper analyses the available hardware, software and network technologies which can be used for creating a positioning system for interior, closed or covered area. The paper analyses technologies which can be used in such distributed systems for the implementation of functionalities that are needed or required in the Indoor Positioning System (IPS). The paper describes the concept of the IPS system. It presents the IPS systems available on the market. It shows the technologies that can be used to implement the IPS system and the analyses of categories which affect the IPS system implementation. The paper demonstrates that none of the technologies analysed meet all of the observed categories while the BLE technology achieves the most favourable results in individual categories.Zbog napretka u razvoju raznih tehnologija koje se mogu koristiti za lociranje, u posljednje vrijeme razvijaju se sustavi koji uključuju programska rješenja za lociranje i navođenje korisnika u unutarnjem, zatvorenom ili natkrivenom prostoru, gdje se postojeće tehnologije za lociranje i sustavi za lociranje i navođenje koje se primjenjuju kod otvorenih, vanjskih prostora, ne mogu koristiti. U radu se analiziraju dostupne hardverske, softverske i mrežne tehnologije kojima je moguće izraditi sustav za unutarnje lociranje, odnosno tehnologije kojima takav distribuirani sustav po svom karakteru i implementiranim funkcijama postaje sustav za lociranje u zatvorenom prostoru (IPS, engl. Indoor Positioning System). Opisan je koncept IPS sustava. Prikazani su gotovi IPS sustavi dostupni na tržištu. Pokazane su tehnologije koje se mogu koristiti za implementaciju IPS-a i izrađena analiza kategorija koje utječu na implementaciju IPS-a. Pokazano je da niti jedna tehnologija ne zadovoljava sve promatrane kategorije, no BLE tehnologija omogućuje ostvarenje najpovoljnijih rezultata po pojedinim kategorijama