|Home \ Graduation Activities \ Post-Graduation Page||Login|
Empowering the user with contextual information: From location infrastructures to augmented reality interfaces
Augmented Reality and Ubiquitous Computing are evolving topics in computer science. In this dissertation, augmented reality is discussed as a ubiquitous interface applied to several events in the real world, namely environmental management, every day’s life and entertainment. Throughout the dissertation, different aspects of the development of augmented reality systems for ubiquitous computing are presented, such as a number of architectures, methods and techniques to ubiquitously locate persons and objects and visualize related information. There are several technologies used to track persons and object, however their capabilities and limitations make each technology more suitable for specific purposes. One example is the limitation presented by GPS, used to track users or objects outdoor. However, GPS sensors have problems when used indoor due to the required line-of-sight with the satellites. Thus, different sensors need to be used to track people and objects indoor. Bluetooth is a technology explored in this dissertation to track persons and objects indoor. However, Bluetooth still reveals some limitations, namely due to the cost of Bluetooth development kits and hardware. In the dissertation, a custom radio tracking system is purposed, reducing costs and augmenting the functionality of the system. Nevertheless, a new challenge rose: How to model location? In this dissertation the agents involved in a location system are discussed as well as how to model location information, whether using symbolic information or geometric information. In a wider spectrum, context is also discussed, taking advantage of the actions performed in the environment and the previous knowledge of user’s characteristics. In the first chapters, the infrastructure required in an augmented reality system is discussed, mainly considering indoor scenarios. Afterwards, the complete system is considered to fully develop augmented reality applications. As stated before, augmented reality is also applied as a ubiquitous interface to be used by environmental engineers while in the field of observation. This work was developed in the scope of the ANTS project, where laptop computers with a head-mounted display and PDAs were used, allowing environmental engineers to grasp information about the surrounding environment. The system explores the capacities and constrains of both approaches to improve the interface with the user. As a proof of concept, three applications were developed. Two applications, one for buildings visualization and another for subsoil structure visualization, use a 3D model and a database in the server side, for the purposes of content and user positioning, and use presentation components to superimpose virtual information over real images in the client side. The remaining application, for pollution dispersion simulation, uses a dispersion pollution model for the purposes of tracking and providing content, in the server side. In the client side, presentation components are used, similarly to the two previous applications. Finally, a mobile wireless augmented reality system for mobile phones is presented. The system uses mobile phones and wireless sensors to supply a seamless augmented experience, without bulky and cumber equipment augmented experience. The system presented also explores two different methods to update the augmented experience in the mobile phone.
Start Date: 2002-04-23
End Date: 2008-06-16
Post-Graduation Student / Researcher / Professor: