Schematisation in Hard-copy Tactile Orientation Maps

This dissertation investigates schematisation of computer-generated tactile orientation maps that support mediation of spatial knowledge of unknown urban environments. Computergenerated tactile orientation maps are designed to provide the blind with an overall impression of their surroundings. Their details are displayed by means of elevated features that are created by embossers and can be distinguished by touch. The initial observation of this dissertation states that only very little information is actually transported through tactile maps owing to the coarse resolution of tactual senses and the cognitive effort involved in the serial exploration of tactile maps. However, the differences between computer-generated, embossed tactile maps and manufactured, deep-drawn tactile maps are significant. Therefore the possibilities and confines of communicating information through tactile maps produced with embossers is a primary area of research. This dissertation has been able to demonstrate that the quality of embossed prints is an almost equal alternative to traditionally manufactured deep-drawn maps. Their great advantage is fast and individual production and (apart from the initial procurement costs for the printer)low price, accessibility and easy understanding without the need of prior time-consuming training. Simplification of tactile maps is essential, even more so than in other maps. It can be achieved by selecting a limited number from all map elements available. Qualitative simplification through schematisation may present an additional option to simplification through quantitative selection. In this context schematisation is understood as cognitively motivated simplification of geometry and synchronised maintenance of topology. Rather than further reducing the number of displayed objects, the investigation concentrates on how the presentation of different forms of streets (natural vs. straightened) and junctions (natural vs. prototypical) affects the transfer of knowledge. In a second area of research, a thesis establishes that qualitative simplification of tactile orientation maps through schematisation can enhance their usability and make them easier to understand than maps that have not been schematised. The dissertation shows that simplifying street forms and limiting them to prototypical junctions does not only accelerate map exploration but also has a beneficial influence on retention performance. The majority of participants that took part in the investigation selected a combination of both as their preferred display option. Tactile maps that have to be tediously explored through touch, uncovering every detail, complicate attaining a first impression or an overall perception. A third area of research is examined, establishing which means could facilitate map readersâ options to discover certain objects on the map quickly and without possessing a complete overview. Three types of aids are examined: guiding lines leading from the frame of the map to the object, position indicators represented by position markers at the frame of the map and coordinate specifications found within a grid on the map. The dissertation shows that all three varieties can be realised by embossers. Although a guiding line proves to be fast in size A4 tactile maps containing only one target object and few distracting objects, it also impedes further exploration of the map (similar to the grid). In the following, advantages and drawbacks of the various aids in this and other applications are discussed. In conclusion the dissertation elaborates on the linking points of all three examinations. They connect and it is argued that cognitively motivated simplification should be a principle of construction for embossed tactile orientation maps in order to support their use and comprehension. A summary establishes the recommendations that result from this dissertation regarding construction of tactile orientation maps considering the limitations through embosser constraints. Then I deliberate how to adapt schematisation of other maps contingent to intended function, previous knowledge of the map reader, and the relation between the time in which knowledge is acquired and the time it is employed. Closing the dissertation, I provide an insight into its confines and deductions and finish with a prospective view to possible transfers of the findings to other applications, e.g. multimedia or interactive maps on pin-matrix displays and devices

Cognitive Principles of Schematisation for Wayfinding Assistance

People often need assistance to successfully perform wayfinding tasks in unfamiliar environments. Nowadays, a huge variety of wayfinding assistance systems exists. All these systems intend to present the needed information for a certain wayfinding situation in an adequate presentation. Some wayfinding assistance systems utilize findings for the field of cognitive sciences to develop and design cognitive ergonomic approaches. These approaches aim to be systems with which the users can effortless interact with and which present needed information in a way the user can acquire the information naturally. Therefore it is necessary to determinate the information needs of the user in a certain wayfinding task and to investigate how this information is processed and conceptualised by the wayfinder to be able to present it adequately. Cognitive motivated schematic maps are an example which employ this knowledge and emphasise relevant information and present it in an easily readable way. In my thesis I present a transfer approach to reuse the knowledge of well-grounded knowledge of schematisation techniques from one externalisation such as maps to another externalization such as virtual environments. A analysis of the informational need of the specific wayfinding task route following is done one the hand of a functional decomposition as well as a deep analysis of representation-theoretic consideration of the external representations maps and virtual environments. Concluding from these results, guidelines for transferring schematisation principles between different representation types are proposed. Specifically, this thesis chose the exemplary transfer of the schematisation technique wayfinding choremes from a map presentation into a virtual environment to present the theoretic requirements for a successful transfer. Wayfinding choremes are abstract mental concepts of turning action which are accessible as graphical externalisation integrated into route maps. These wayfinding choremes maps emphasis the turning action along the route by displaying the angular information as prototypes of 45° or 90°. This schematisation technique enhances wayfinding performance by supporting the matching processes between the map representation and the internal mental representation of the user. I embed the concept of wayfinding choremes into a virtual environment and present a study to test if the transferred schematisation technique also enhance the wayfinding performance. The empirical investigations present a successful transfer of the concept of the wayfinding choremes. Depending on the complexity of the route the embedded schematization enhance the wayfinding performance of participants who try to follow a route from memory. Participants who trained and recall the route in a schematised virtual environment make fewer errors than the participants of the unmodified virtual world. This thesis sets an example of the close research circle of cognitive behavioural studies to representation-theoretical considerations to applications of wayfinding assistance and their evaluations back to new conclusions in cognitive science. It contributes an interdisciplinary comprehensive inspection of the interplay of environmental factors and mental processes on the example of angular information and mental distortion of this information

Improving the acquisition of spatial knowledge when navigating with an augmented reality navigation system

Navigation is a process humans use whenever they move. There are more complex tasks like finding our way in a new city and easier tasks like getting a cup of coffee. Daniel Montello (2005, p. 2) defines navigation as “the coordinated and goal-directed movement through the environment by organisms or intelligent machines”. When navigating in an unknown environment, humans often rely on assisted wayfinding by some sort of navigation aid. During the last years, the preferred navigation system shifted from printed maps to electronic and thus dynamic navigation systems on our smartphones. Recently, mixed reality and virtual reality approaches such as augmented reality (AR) have become an interesting alternative to the classical smartphone navigation. This although, the first attempts to AR were already made in the middle of the last century. The major advantages of AR navigation systems are that localisation and above all also tracking tasks are made by the system and that the navigation instructions are directly laid into the environment. The main drawback, on the other hand, is that the more tasks are made by the system, the less spatial learning is achieved by a human. The goal of this thesis is to examine ways to improve the process of spatial learning on assisted wayfinding. An experiment where participants are guided through a test environment by an AR system is set up to test these ways. After completing the route, the participants had to fill out a questionnaire about landmarks and intersections, which they had encountered on the route. The concrete goals of the thesis are to find out (1) whether giving more spatial information will improve spatial learning, (2) whether the placement of navigation instructions has an influence (positive or negative) on spatial learning, (3) whether the type of landmark has an influence on how well it is recalled and (4) how well landmark and route knowledge is built after having completed the route once. The results of the experiment suggest that giving background information to certain landmarks do not lead to a significantly different performance in spatial learning (p = .691). The result could also show that there is no difference whether a landmark is highlighted by a navigation instruction or not (p = .330). The analyses of landmark and route knowledge has shown that the participants have built less landmark knowledge than route knowledge after the run, as they have approx. 50 % of the landmarks correct but 67 % of the intersections. Interesting and in this case significant is the difference between the types of landmarks (p = .018). 3D objects are recalled much better than other landmarks. Also significant (p = 6.14e-3) but unfortunately not very robust is the influence of the age on the acquisition of route knowledge. As the age distribution is very unbalanced, these results have to be interpreted with caution. Following the findings of this thesis, it is suggested to conduct a series of experiments with an eye tracker to learn more about how the visual focus of people using AR as a wayfinding assistance behaves

Cognitive Principles of Schematisation for Wayfinding Assistance

People often need assistance to successfully perform wayfinding tasks in unfamiliar environments. Nowadays, a huge variety of wayfinding assistance systems exists. All these systems intend to present the needed information for a certain wayfinding situation in an adequate presentation. Some wayfinding assistance systems utilize findings for the field of cognitive sciences to develop and design cognitive ergonomic approaches. These approaches aim to be systems with which the users can effortless interact with and which present needed information in a way the user can acquire the information naturally. Therefore it is necessary to determinate the information needs of the user in a certain wayfinding task and to investigate how this information is processed and conceptualised by the wayfinder to be able to present it adequately. Cognitive motivated schematic maps are an example which employ this knowledge and emphasise relevant information and present it in an easily readable way. In my thesis I present a transfer approach to reuse the knowledge of well-grounded knowledge of schematisation techniques from one externalisation such as maps to another externalization such as virtual environments. A analysis of the informational need of the specific wayfinding task route following is done one the hand of a functional decomposition as well as a deep analysis of representation-theoretic consideration of the external representations maps and virtual environments. Concluding from these results, guidelines for transferring schematisation principles between different representation types are proposed. Specifically, this thesis chose the exemplary transfer of the schematisation technique wayfinding choremes from a map presentation into a virtual environment to present the theoretic requirements for a successful transfer. Wayfinding choremes are abstract mental concepts of turning action which are accessible as graphical externalisation integrated into route maps. These wayfinding choremes maps emphasis the turning action along the route by displaying the angular information as prototypes of 45° or 90°. This schematisation technique enhances wayfinding performance by supporting the matching processes between the map representation and the internal mental representation of the user. I embed the concept of wayfinding choremes into a virtual environment and present a study to test if the transferred schematisation technique also enhance the wayfinding performance. The empirical investigations present a successful transfer of the concept of the wayfinding choremes. Depending on the complexity of the route the embedded schematization enhance the wayfinding performance of participants who try to follow a route from memory. Participants who trained and recall the route in a schematised virtual environment make fewer errors than the participants of the unmodified virtual world. This thesis sets an example of the close research circle of cognitive behavioural studies to representation-theoretical considerations to applications of wayfinding assistance and their evaluations back to new conclusions in cognitive science. It contributes an interdisciplinary comprehensive inspection of the interplay of environmental factors and mental processes on the example of angular information and mental distortion of this information

Auditory Displays and Assistive Technologies: the use of head movements by visually impaired individuals and their implementation in binaural interfaces

Visually impaired people rely upon audition for a variety of purposes, among these are the use of sound to identify the position of objects in their surrounding environment. This is limited not just to localising sound emitting objects, but also obstacles and environmental boundaries, thanks to their ability to extract information from reverberation and sound reflections- all of which can contribute to effective and safe navigation, as well as serving a function in certain assistive technologies thanks to the advent of binaural auditory virtual reality. It is known that head movements in the presence of sound elicit changes in the acoustical signals which arrive at each ear, and these changes can improve common auditory localisation problems in headphone-based auditory virtual reality, such as front-to-back reversals. The goal of the work presented here is to investigate whether the visually impaired naturally engage head movement to facilitate auditory perception and to what extent it may be applicable to the design of virtual auditory assistive technology. Three novel experiments are presented; a field study of head movement behaviour during navigation, a questionnaire assessing the self-reported use of head movement in auditory perception by visually impaired individuals (each comparing visually impaired and sighted participants) and an acoustical analysis of inter-aural differences and cross- correlations as a function of head angle and sound source distance. It is found that visually impaired people self-report using head movement for auditory distance perception. This is supported by head movements observed during the field study, whilst the acoustical analysis showed that interaural correlations for sound sources within 5m of the listener were reduced as head angle or distance to sound source were increased, and that interaural differences and correlations in reflected sound were generally lower than that of direct sound. Subsequently, relevant guidelines for designers of assistive auditory virtual reality are proposed

Mental maps and the use of sensory information by blind and partially sighted people

This article aims to fill an important gap in the literature by reporting on blind and partially sighted people's use of spatial representations (mental maps) from their perspective and when travelling on real routes. The results presented here were obtained from semi-structured interviews with 100 blind and partially sighted people in five different countries. They are intended to answer three questions about the representation of space by blind and partially sighted people, how these representations are used to support travel, and the implications for the design of travel aids and orientation and mobility training. They show that blind and partially sighted people do have spatial representations and that a number of them explicitly use the term mental map. This article discusses the variety of approaches to spatial representations, including the sensory modalities used, the use of global or local representations, and the applications to support travel. The conclusions summarize the answers to the three questions and include a two-level preliminary classification of the spatial representations of blind and partially sighted people

Comparing written and photo-based indoor wayfinding instructions through eye fixation measures and user ratings as mental effort assessments

The use of mobile pedestrian wayfinding applications is gaining importance indoors. However, compared to outdoors, much less research has been conducted with respect to the most adequate ways to convey indoor wayfinding information to a user. An explorative study was conducted to compare two pedestrian indoor wayfinding applications, one text-based (Sole-Way) and one image-based (Eyedog), in terms of mental effort. To do this, eye tracking data and mental effort ratings were collected from 29 participants during two routes in an indoor environment. The results show that both textual instructions and photographs can enable a navigator to find his/her way while experiencing no or very little cognitive effort or difficulties. However, these instructions must be in line with a user's expectations of the route, which are based on his/her interpretation of the indoor environment at decision points. In this case, textual instructions offer the advantage that specific information can be explicitly and concisely shared with the user. Furthermore, the study drew attention to potential usability issues of the wayfinding aids (e.g. the incentive to swipe) and, as such, demonstrated the value of eye tracking and mental effort assessments in usability research

Route schematization with landmarks

Predominant navigation applications make use of a turn-by-turn instructions approach and are mostly supported by small screen devices. This combination does little to improve users\u27 orientation or spatial knowledge acquisition. Considering this limitation, we propose a route schematization method aimed for small screen devices to facilitate the readability of route information and survey knowledge acquisition. Current schematization methods focus on the route path and ignore context information, specially polygonal landmarks (such as lakes, parks, and regions), which is crucial for promoting orientation. Our schematization method, in addition to the route path, takes as input: adjacent streets, point-like landmarks, and polygonal landmarks. Moreover, our schematic route map layout highlights spatial relations between route and context information, improves the readability of turns at decision points, and the visibility of survey information on small screen devices. The schematization algorithm combines geometric transformations and integer linear programming to produce the maps. The contribution of this paper is a method that produces schematic route maps with context information to support the user in wayfinding and orientation

Personal Wayfinding Assistance

We are traveling many different routes every day. In familiar environments it is easy for us to find our ways. We know our way from bedroom to kitchen, from home to work, from parking place to office, and back home at the end of the working day. We have learned these routes in the past and are now able to find our destination without having to think about it. As soon as we want to find a place beyond the demarcations of our mental map, we need help. In some cases we ask our friends to explain us the way, in other cases we use a map to find out about the place. Mobile phones are increasingly equipped with wayfinding assistance. These devices are usually at hand because they are handy and small, which enables us to get wayfinding assistance everywhere where we need it. While the small size of mobile phones makes them handy, it is a disadvantage for displaying maps. Geographic information requires space to be visualized in order to be understandable. Typically, not all information displayed in maps is necessary. An example are walking ways in parks for car drivers, they are they are usually no relevant route options. By not displaying irrelevant information, it is possible to compress the map without losing important information. To reduce information purposefully, we need information about the user, the task at hand, and the environment it is embedded in. In this cumulative dissertation, I describe an approach that utilizes the prior knowledge of the user to adapt maps to the to the limited display options of mobile devices with small displays. I focus on central questions that occur during wayfinding and relate them to the knowledge of the user. This enables the generation of personal and context-specific wayfinding assistance in the form of maps which are optimized for small displays. To achieve personalized assistance, I present algorithmic methods to derive spatial user profiles from trajectory data. The individual profiles contain information about the places users regularly visit, as well as the traveled routes between them. By means of these profiles it is possible to generate personalized maps for partially familiar environments. Only the unfamiliar parts of the environment are presented in detail, the familiar parts are highly simplified. This bears great potential to minimize the maps, while at the same time preserving the understandability by including personally meaningful places as references. To ensure the understandability of personalized maps, we have to make sure that the names of the places are adapted to users. In this thesis, we study the naming of places and analyze the potential to automatically select and generate place names. However, personalized maps only work for environments the users are partially familiar with. If users need assistance for unfamiliar environments, they require complete information. In this thesis, I further present approaches to support uses in typical situations which can occur during wayfinding. I present solutions to communicate context information and survey knowledge along the route, as well as methods to support self-localization in case orientation is lost