DS Online: Works in Progress

Current middleware technology for ubiquitous computing connects mobile computers to services in the environment. This is often insufficient because it doesn't address the issue of services depending on other services. The DWARF framework offers a decentralized approach to configuring and coordinating interdependent services. Typical ubiquitous computing scenarios let mobile users access stationary services. This creates star-shaped dynamic connections between a user device—typically a PDA or a wearable computer—and smart devices in the environment. For this kind of configuration, current middleware can discover services and set up communication. However, this approach is insufficient for highly mobile and collaborative applications involving several users with diverse mobile and stationary hardware. Services the environment offers to users might depend on services that another user's hardware offers. This poses a new challenge to the middleware: it must set up connections between interdependent ad hoc services. We have used our research platform—DWARF (Distributed Wearable Augmented Reality Framework 1)—to build distributed mobile multimedia and augmented reality systems consisting of decentralized services. Augmented reality systems must determine the position and orientation of a user's head and other moving objects in real time and use this information to overlay 3D virtual objects onto real scenes. Consider just a small part of a mobile augmented reality scenario.