Abstract
We aim to increase the density of spatial memory which is an interface to achieve storage of and access information in intelligent spaces. To realize this, we propose a hierarchical structure of the spatial memory. To build the hierarchical structure, we define the global spatial memory and the local spatial memory. The global spatial memory consists of SKT (Spatial-Knowledge-Tag) which is defined in a global coordinate system. The local spatial memory is defined as local-SKTs connected with a global SKT. A local-SKT is defined in a coordinate system of the head-mounted display. To interact with and to operate the hierarchical spatial memory intuitively, we use see-through head-mounted display and Leap motion.