Design and Implementation of Intelligent Space: a Component Based Approach

In recent years, the research field on smart environments, which are spaces with multiple embedded and networked sensors and actuators, has been expanding (Cook & Das, 2004). The smart environments observe the spaces using distributed sensors, extract useful information from the obtained data and provide various services to users. Such an environment is also referred to as smart space, intelligent environment, etc., and many researchers have developed smart environments for providing informative services to the users (e.g. support during meeting (Johanson et al., 2002), health care (Nishida et al., 2000), support of the elderly (Mynatt et al., 2004), information display using a pan-tilt projector (Mori et al., 2004)). On the other hand, smart environments are also used for support of mobile robots that work in complicated human living environments. In this type of smart environments, mobile robots inside the space get necessary information from multiple distributed sensors and various functions such as localization, path planning and humanrobot interaction are performed with the support of the system (Mizoguchi et al., 1999), (Sgorbissa & Zaccaria, 2004), (Koide et al., 2004). Aiming to provide both informative and physical services to the users, we have also been developing a smart environment, called Intelligent Space (iSpace), since 1996 (Lee & Hashimoto, 2002). Fig. 1 shows the concept of iSpace. In iSpace, not only sensor devices but also sensor nodes are distributed in the space because it is necessary to reduce the network load in the large-scale network and it can be realized by processing the raw data in each sensor node before collecting information. We call the sensor node devices distributed in the space DINDs (Distributed Intelligent Network Device). A DIND consists of three basic components: sensors, processors and communication devices. The processors deal with the sensed data and extract useful information about objects (type of object, three dimensional position, etc.), users (identification, posture, activity, etc.) and the environment (geometrical shape, temperature, emergency, etc.). The network of DINDs can realize the observation and understanding of the events in the whole space. Based on the extracted and fused information, actuators such as displays or projectors embedded in the space provide informative services to users. In iSpace, mobile robots are also used as actuators to provide physical services to the users and for them we use the name mobile agents. The mobile agent can utilize the intelligence of iSpace. By using distributed sensors and computers, the 6