Learning cognitive maps: Finding useful structure in an uncertain world

In this chapter we will describe the central mechanisms that influence how people learn about large-scale space. We will focus particularly on how these mechanisms enable people to effectively cope with both the uncertainty inherent in a constantly changing world and also with the high information content of natural environments. The major lessons are that humans get by with a less is more approach to building structure, and that they are able to quickly adapt to environmental changes thanks to a range of general purpose mechanisms. By looking at abstract principles, instead of concrete implementation details, it is shown that the study of human learning can provide valuable lessons for robotics. Finally, these issues are discussed in the context of an implementation on a mobile robot. © 2007 Springer-Verlag Berlin Heidelberg

Advances towards behaviour-based indoor robotic exploration

215 p.The main contributions of this research work remain in object recognition by computer vision, by one side, and in robot localisation and mapping by the other. The first contribution area of the research address object recognition in mobile robots. In this area, door handle recognition is of great importance, as it help the robot to identify doors in places where the camera is not able to view the whole door. In this research, a new two step algorithm is presented based on feature extraction that aimed at improving the extracted features to reduce the superfluous keypoints to be compared at the same time that it increased its efficiency by improving accuracy and reducing the computational time. Opposite to segmentation based paradigms, the feature extraction based two-step method can easily be generalized to other types of handles or even more, to other type of objects such as road signals. Experiments have shown very good accuracy when tested in real environments with different kind of door handles. With respect to the second contribution, a new technique to construct a topological map during the exploration phase a robot would perform on an unseen office-like environment is presented. Firstly a preliminary approach proposed to merge the Markovian localisation in a distributed system, which requires low storage and computational resources and is adequate to be applied in dynamic environments. In the same area, a second contribution to terrain inspection level behaviour based navigation concerned to the development of an automatic mapping method for acquiring the procedural topological map. The new approach is based on a typicality test called INCA to perform the so called loop-closing action. The method was integrated in a behaviour-based control architecture and tested in both, simulated and real robot/environment system. The developed system proved to be useful also for localisation purpose

Problems and solutions in middle size robot soccer: a review

A review of current scientific and technological problems encountered in building and programming middle size soccer robots is made in this paper. Solutions and solution trends to the problems, as presented by different teams, are also examined. Perceptual systems of individual robots, in particular with respect to object location, communications between robot players, decision making with regard to game strategy and behaviour generation, and, finally, actuation, are the topics dealt with. This makes for a wide perspective on the actual state of the art of middle size soccer robots

How do individuals with Williams syndrome learn a route in a real-world environment?

Individuals with Williams syndrome (WS) show a specific deficit in visuo-spatial abilities. This finding, however, is mainly based on performance on small-scale laboratory-based tasks. This study investigated large-scale route learning in individuals with WS and two matched control groups (moderate learning difficulty group [MLD], typically developing group [TD]). In a non-labelling and a labelling (verbal information provided along the route) condition, participants were guided along one of two unfamiliar 1 km routes with 20 junctions, and then retraced the route themselves (two trials). The WS participants performed less well than the other groups, but given verbal information and repeated experience they learnt nearly all of the turns along the route. The extent of improvement in route knowledge (correct turns) in WS was comparable to that of the control groups. Relational knowledge (correctly identifying spatial relationships between landmarks), compared to the TD group, remained poor for both the WS and MLD groups. Assessment of the relationship between performance on the large-scale route learning task to that on three small-scale tasks (maze learning, perspective taking, map use) showed no relationship for the TD controls, and only a few non-specific associations in the MLD and WS groups

The signing body: Extensive sign language practice shapes the size of hands and face

The representation of the metrics of the hands is distorted but is susceptible to malleability due to expert dexterity (magicians) and long-term tool use (baseball players). However, it remains unclear whether modulation leads to a stable representation of the hand that is adopted in every circumstance, or whether the modulation is closely linked to the spatial context where the expertise occurs. To this aim, a group of 10 experienced Sign Language (SL) interpreters were recruited to study the selective influence of expertise and space localisation in the metric representation of hands. Experiment 1 explored differences in hands’ size representation between the SL interpreters and 10 age-matched controls in near-reaching (Condition 1) and far-reaching space (Condition 2), by using the localisation task. SL interpreters presented reduced hand size in near-reaching condition, with characteristic underestimation of finger lengths, and reduced overestimation of hands and wrists widths in comparison with controls. This difference was lost in far-reaching space, confirming the effect of expertise on hand representations is closely linked to the spatial context where an action is performed. As SL interpreters are also experts in the use of their face with communication purposes, the effects of expertise in the metrics of the face were also studied (Experiment 2). SL interpreters were more accurate than controls, with overall reduction of width overestimation. Overall, expertise modifies the representation of relevant body parts in a specific and context-dependent manner. Hence, different representations of the same body part can coexist simultaneously

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