A lightweight indoor location model for sentient artefacts using sentient artefacts

Our approach towards context awareness is to use sensor augmented daily life objects surrounding us for extracting context information and for providing ambient services. Some of these artefacts are static in nature and have designated location, like a bed in the bedroom, a refrigerator in the kitchen, etc. Utilizing this characteristics, we present "Spreha", a light weight hierarchical location model where static artefacts are used as reference points for identifying mobile artefacts like a chair, a watch, a lamp, etc. The model is organized in a tree structure representing the containment relationship and is independent of underlying sensing infrastructure. A prototype implementation of the model has been constructed as a pluggable module of a generic middleware using Bluetooth technology. This paper discusses about the design, architecture and findings of the prototype implementation.