Bernhard Schmitz

Acquisition and Presentation of Diverse Spatial Context Data for Blind Navigation

In order to allow blind people independent navigation in unknown areas, we have developed a navigation system that seamlessly integrates both static maps and dynamic location-based textual information from a variety of sources. Each information source requires a different kind of acquisition technique. The acquired information is integrated by a context management platform and then presented to the user on a tactile-acoustical map depending on the sources available for his current position. Positioning is achieved by a combination of an inertial tracking system, RFID technology and GPS and the user is guided to a desired destination by speech output and a hap tic cane. The resulting system is the first of its kind to integrate a variety of maps and other accumulated location-based information on a unified interface for blind people.

Making digital maps accessible using vibrations

In order to allow blind and deafblind people to use and explore electronically available maps, we have developed a system that displays maps in a tactile way using a standard rumble gamepad. The system is intended for both on-site and off-site use and therefore includes mechanisms for getting overviews of larger regions as well as for the exploration of small areas.

Application of a Driver Intention Recognition Algorithm on a Pedestrian Intention Recognition and Collision Avoidance System

Driver intention recognition can enhance the driver-vehicle interaction by offering more intuitive assistance and automated driving support. Especially urban environments require fast reactions and hence assistance systems which act in accordance to driver’s intentions. Assistance should provide comfortably timed warnings only in situations when drivers really need this support and not in situations when the driver is already intending to react to a thread.

Individualized Route Planning and Guidance Based on Map Content Transformations

We have created a system of rule-based map content transformations that allows to create maps that are better fit for specific purposes and user groups than the base material. In this paper we demonstrate the application of the map content transformations in route planning and route guidance of a navigation system for specific user groups. We show that it is possible to create maps that are better suited to these tasks than the material on which they are based.

Creating task-specific maps with map content transformations

Many mobile applications rely on maps in some form. However, the kind of map that is needed depends on the application and also on the user. However, conventional mapping systems employ on a one-size-fits-all approach, settling on compromises that work reasonably well for many applications. In order to deliver the exact kind of map that is required in a specific situation, we introduce a method that transforms OpenStreetMap data according to scripts that can be specified by the user. The result has the same data format as the original, but is adapted to the specific use case that the writer of the script had in mind. Thus, different representations of the same base data can be constructed when it is needed. As an example case of a user group that can profit from such content transformations, we conducted a user study with blind people which shows that they can benefit from transformed maps.

Rule-based transformation of map data

The use of map data is often limited by the specific format and level of detail in which it is stored. We present a method that uses rule-based two dimensional scripting to enhance map data according to individual requirements of the application or the user. The method is demonstrated on OpenStreetMap data.

Combination of map-supported particle filters with activity recognition for blind navigation

By implementing a combination of an activity recognition with a map-supported particle filter we were able to significantly improve the positioning of our navigation system for blind people. The activity recognition recognizes walking forward or backward, or ascending or descending stairs. This knowledge is combined with knowledge from the maps, i.e. the location of stairs. Different implementations of the particle filter were evaluated regarding their ability to compensate for sensor drift.

An OpenStreetMap Editing Interface for Visually Impaired Users Based on Geo-semantic Information

We present a system for editing OpenStreetMap data, which is based on the idea that common-sense preconceptions about the world can be encoded semantically and thus used in conjunction with preexisting data about an area to predict probable changes. The system can thus reduce the number of OpenStreetMap tags from which the user can choose.

Application design for an eye tracking analysis based on visual analytics

With this demo we show a new application design for analyzing eye tracking experiments following the visual analytics approach. This application design allows users to analyze large eye tracking data sets efficiently and to find interesting patterns in eye movement data as well as correlations between eye movements and other data streams. We describe the main characteristics of the implemented visualizations and pattern recognition algorithms, present the interaction concept and demonstrate the main analysis features in a use case concerning the development of a driver assistance system.

Navigation systems for special user groups

With the advent of smartphones and apps, navigation systems have become one of the most widely used mobile applications on the planet. At the same time there are some user groups, especially among people with disabilities, for whom the benefit of navigation systems is even greater than for the average user. Even though navigation systems for those smaller user groups have become available in recent years and are of great help to their users, those navigation systems are currently not as great a tool as they could potentially be, as has been shown by prototypes in smaller research projects. From a user perspective, navigation systems give feedback about the current location, receive input about a desired destination, and guide the user to this destination. In addition to that, the system itself needs to determine the position and calculate a route to the destination. For all of these navigational tasks, the systems needs a world model, be it a map or another representation of the world. Many existing projects have concentrated on adapting these navigational tasks to the specific requirements of a user group, and even though this thesis contributes to these efforts, especially for blind users, its main contribution lies in a different approach. The thesis supposes that the world model provides a great leverage for adapting navigation systems to the specific requirements of the users, as the world model has influence on all navigational tasks and therefore is an integral part of all modern navigation systems. Due to this importance, the world models of currently existing special navigation systems for people with disabilities often suffer from one of two distinct problems: If the model is specifically built for the intended purpose, e.g. a navigation system for a defined disability, it is only available in a confined area. This is mostly the case with research systems. Commercially available systems on the other hand strive to cover as large an area as possible, but have to accept certain drawbacks regarding the world models applicability for the specific purpose. Ideally, a world model for special navigation systems is both available world-wide and specifically built or at least adapted for the intended purpose. This thesis introduces a way of integrating both requirements. A world model that is widely available and used by many people builds a common base for the navigation system. This ensures the availability and currentness of the data. This world model is then changed individually with Map Content Transformations, which were developed specifically for this purpose. These Map Content Transformations combine data that is implicitly present in the base data with user specific requirements encoded into the transformation rules and thus adapts the world model according to both the requirements of the user and of the intended navigational tasks. It is shown that these adaptations of the world model can have positive influence on all navigational tasks and can, together with the incremental advances regarding the navigational tasks themselves, create an important step towards individualized navigation systems that optimally support their users in their spatial tasks. Even though in this thesis Map Content Transformations and their usages are applied to the field of navigation for people with disabilities, they have the potential to be used in a variety of applications based on spatial data. Begunstigt durch die weite Verbreitung von Smartphones und Apps sind Navigationssysteme zu einer weitverbreiteten mobilen Anwendung geworden. Gleichzeitig gibt es einige Nutzergruppen, insbesondere unter behinderten Menschen, fur die die Vorteile von Navigationssystemen sogar noch groser als fur den durchschnittlichen Nutzer sind. Auch wenn in den letzten Jahren Navigationssysteme fur diese kleineren Nutzergruppen erhaltlich geworden sind und ihren Nutzern oft eine grose Hilfe sind, so konnen sie doch ihr volles Potential als Hilfsmittel nicht entfalten. Nur einige Forschungsprototypen liesen bisher dieses volle Potential erkennen. Aus der Sicht eines Benutzers geben Navigationssysteme Ruckmeldung uber den aktuellen Standort, erhalten eine Zieleingabe und fuhren den Nutzer dann zum gewunschten Ziel. Daruber hinaus muss das System selbst den aktuellen Standort feststellen und den bestmoglichen Weg zum Ziel berechnen. Fur all diese Navigationsaufgaben benotigt das System ein Umgebungsmodell, sei es in Form einer Karte oder einer anderen Reprasentation. Viele existierende Projekte konzentrieren sich darauf, diese Navigationsaufgaben an die speziellen Anforderungen einer bestimmten Nutzergruppe anzupassen. Auch die vorliegende Arbeit wirkt an den Bestrebungen in dieser Richtung mit, insbesondere fur blinde Nutzer, ihr Hauptbeitrag jedoch liegt in einen anderen Ansatz. Diese Arbeit geht davon aus, dass das Umgebungsmodell einen grosen Einfluss auf die Navigation hat, und daher dazu genutzt werden kann, Navigationssysteme an die spezifischen Anforderungen der Benutzer anzupassen, weil das Umgebungsmodell alle Navigationsaufgaben beeinflusst und daher ein integraler Bestandteil aller modernen Navigationssysteme ist. Aufgrund dieser Wichtigkeit leiden aktuelle Navigationssysteme fur Menschen mit Behinderung oft an einem von zwei gegensatzlichen Problemen: Wenn das Umgebungsmodell speziell fur den angedachten Einsatzzweck, beispielsweise ein Navigationssystem fur eine bestimmte Behinderung, erstellt wurde, ist es nur fur ein eng umrissenes Gebiet verfugbar. Dies ist meist bei Forschungsprototypen der Fall. Kommerziell erhaltliche Systeme hingegen versuchen, ein moglichst weitraumiges Gebiet zu umfassen, mussen dafur aber einige Nachteile bezuglich der Eignung des Umgebungsmodells fur den gewunschten Einsatzzweck in Kauf nehmen. Im Idealfall ist ein Umgebungsmodell sowohl weltweit verfugbar als auch fur den gewunschten Einsatzzweck erstellt oder zumindest angepasst. Diese Arbeit stellt eine Moglichket vor, diese beiden Anforderungen vereinbar zu machen. Ein Umgebungsmodell, das weltweit verfugbar ist und von vielen Menschen genutzt wird, bildet die allgemeine Basis fur das Navigationssystem. Dadurch wird sichergestellt, dass die Daten verfugbar und so aktuell wie moglich sind. Dieses Umgebungsmodell wird dann anhand von regelbasierten Transformationen des Karteninhalts, die speziell zu diesem Zweck entwickelt wurden, transformiert. Diese Transformationen des Karteninhalts kombinieren dabei Daten, die implizit in den Basisdaten vorhanden sind, mit nutzerspezifischen Anforderungen, die in den Transformationsregeln hinterlegt sind. Dadurch wird das Umgebungsmodell an die Anforderungen des Benutzers und der intendierten Navigationsaufgabe angepasst. Es wird gezeigt, dass diese Anpassungen des Umgebungsmodell einen positiven Einfluss auf alle Navigationsaufgaben haben konnen und zusammen mit den anderen vorgestellten Fortschritten bei den Navigationsaufgaben einen wichtigen Schritt hin zu individualisierten Navigationssystemen darstellen, die ihre Nutzer optimal unterstutzen. Auch wenn die Transformationen des Karteninhalts hier fur die Navigation von Menschen mit Behinderung verwendet werden, haben sie doch das Potential in verschiedenen anderen ortsabhangigen Anwendungen eingesetzt zu werden.