|Augmented reality haptic feedback force feedback image processing assistive technologies GIS|
In this work, a new medium to display spatial structures to blind people is presented: virtual tactile maps. A virtual tactile map is a planar, computer-based medium for the display of spatial data which is operated by touch. Data is presented acoustically and via force feedback. The constructive spatial exploration approach is introduced. This is a novel technique to learn spatial information through guided piece-wise assembly of a physical representation with the aid of an interactive computer system. Methods for constructive exploration of virtual tactile maps are presented, by which haptic spatial models can be explored and learned. The approaches are implemented through two different interaction techniques: a system with physical building blocks being tracked by an image processing system, on the one hand, and a system with force feedback for the three-dimensional haptic display of simulated building blocks on the other hand. The design and implementation of systems for constructive exploration are described and novel methods to adapt digital map data to the two output devices are presented. The formal evaluation of the first approach and a small test of the second approach are described, which show the usability of the systems.