ACTITUDINALES ( ) Preparan y presentan

Streitz et al. developed the concept of Cooperative Buildings [153] to provide exible and dynamic environments that provide cooperative workspaces supporting communication and collaboration between users. Their aim was not only to support human-computer interactions but to assist in human-human cooperation and communication by using real world artifacts as the interface to information and as the means of supporting the collaboration and commu- nication between users. iLand [154] is the realisation of this concept and provides a workspace for assisting human creativity within a meeting scenario. It uses computer-augmented objects - Roomware [153] - to provide information and support for group and individual interaction within the iLand environment. In taking this approach Streitz et al. have used a human- centered design where the human may also be part of a group or organisation.

2.3.2.1 Roomware

The concept of Roomware [153] was conceived by Streitz et al. as a way of creating exible, dynamic landscapes, that could integrate real architectural spaces with virtual information spaces in a way that supports the cooperation and communication of one human to an- other. So far Streitz et al. have created a number of Roomware components; an interactive electronic wall (DynaWall), an interactive electronic table (InteracTable), networked chairs (CommChairs), and a smaller interactive table called the ConnecTable. All of which can be seen in Figure 2.2.

Figure 2.2: Roomware: ConnecTable, CommChair, DynaWall, InteracTable.

constructed from three touch sensitive rear-projected whiteboards. The display is used in iLand to aid teams to display and interact with large amounts of information. Users interact with the display by using gestures to create, move, and delete information objects from the display. The CommChairs are mobile chairs with either an in-built computer or docking point for a laptop. The chair allows users to communicate and share information with people in other chairs or with other Roomware components such as DynaWall. From the chair the user can annotate these remote workspaces as well as making their own personal notes within their own private workspace. The InteracTable is a table with a vertical touch-sensitive display embedded into the top of the table. It is designed to be used by groups of up to six people. Gestures are used by the group to manipulate the dierent information objects and annotations can be provided through the use of voice and/or pen. ConnecTable is a smaller version of the InteracTable and has been designed by Streitz et al. for individual work or for cooperation between small groups. Each of these components, with the exception of DynaWall, use wireless communication and have their own independent power source. This allows the users to congure the Roomware components in the desired way. However, the movement is limited to the range of the wireless communication as iLand is based on a client/server architecture.

2.3.2.2 iLand Infrastructure

Streitz et al. use the Roomware components to support the collaboration and communica- tion between users in the iLand environment. In order to support the functionality of these components Tandler has developed the Basic Environment for Active Collaboration with Hypermedia (BEACH) [156, 157] system for supporting synchronous collaboration and inter- action between Roomware components. BEACH is horizontally organised in four layers - core, models, generic, modules - which dene increasing levels of abstraction and vertically by ve models - interaction model, physical model, user-interface model, tool model, and document model - that separate the basic concerns of the infrastructure. The abstractions provided by BEACH, in particular the physical model, help to remove the low-level complexities of dealing with the real world and so aid the physical integration of the Roomware components into the iLand environment.

To ensure a clear separation of concerns Tandler uses dierent models for interaction, the physical environment, user interface, tools, and documents. The document model describes all objects related to a document. The tool model provides descriptions of tools that can be used in conjunction with the user interface, for instance, toolbars and document browsers. The user interface model denes alternative user interfaces that can be used with each device in the iLand environment. The physical model provides representations of the real world. The interaction model denes the means by which users can control and manipulate the dierent components of the system. All the models are implemented as shared objects except for the interaction model object which is local to each Roomware component. The sharing of objects allows for several users or devices to access the objects at the same time.

The core layer of BEACH, which is based on COAST [145], provides the means of achiev- ing this. COAST provides BEACH with a shared-object space that allows the distribution, replication, and synchronisation of objects across the iLand environment. The core layer also provides additional functionality for event handling and sensor management. The layer ensures the spontaneous interoperability between the Roomware components in the iLand environment. However, COAST is based on a client/server architecture where each of the Roomware components runs one or more BEACH clients that synchronise with a central

server. Such an architecture may be subject to issues of scalability and reliability due to the use of centralised components to coordinate the Roomware components.

Directly above the core layer is the model layer. The model layer provides an implemen- tation of the basic models that are used in implementing the higher layers. For instance, the layer provides interfaces for manipulating documents, for user interfaces, and models for dierent styles of interaction within the iLand environment. Based on the model layer the generic layer provides a set of components that support the basic functionality that is required for supporting most teamwork and meeting situations. For example, the components at this level support informal handwritten scribbles, as well as private and public workspaces for collaboration between users. In additional to the generic layer is the modules layer, which provides extra support for dening functionality for specic tasks not handled by the compo- nents in the generic layer. Currently, this layer is used in iLand to support creative teams in collecting ideas during brain storming sessions.

It should be noted that BEACH requires a considerable amount of computational re- sources and is not suitable for small devices such as PDAs. Also, the infrastructure requires continuous network connectively to support the synchronous collaboration between devices in the iLand environment. This does not lead to a robust pervasive computing system as wireless communication used in the roomware components is not considered to be reliable. Also, the infrastructure is primarily built for supporting meetings, braining-storming sessions and it would appear that it may be dicult to use it develop other types of environments. 2.3.2.3 Developing Roomware Components with BEACH

Developing pervasive computing environments with BEACH is centered around the creation of Roomware components for the environment. In the iLand environment a number of such components - DynaWall, InterTable, CommChairs, and ConnecTable - were developed to assist groups of people in creative sessions. In BEACH the development of these Roomware components is centered on the generic layer as this layer dene the concrete classes that are used to implement the generic support for the components. For example, the DynWall consists of three machines each with a wall mounted display. The physical model at this layer would

dene a roomware component of three machines with their displays combined into one large display area. The user interface model would dene the display as one large segment in which a document browser is placed. The document model would dene the workspace.

2.3.2.4 Summary

Ambiente's Cooperative Project have developed a system for supporting the communication and collaboration between groups of users in a workspace environment. Their approach is cen- tered around the concept of Cooperative Buildings [153] and the use of computer-augmented objects to provide information and support for group and individual interaction in a pervasive computing environment. The iLand [154] environment is the initial prototype of the concept, which is based on a collection of Roomware components that are supported by BEACH. While BEACH is eective in abstracting the complexities of supporting the collaboration of users there are concerns with its ability to scale to larger a environment and to provide a robust service in the face disturbances within the environment. The work presented in this thesis looke to address these issues through the use of techniques based on the natural phenomena of stigmergy.