Frank Siegemund and Christian Flörkemeier
Passive RFID technology and unobtrusive Bluetooth-enabled active tags are means to augment products and everyday objects with information technology invisible to human users. This paper analyzes general interaction patterns in such pervasive computing settings where information about the user's context is derived by a combination of active and passive tags present in the user's environment. We distinguish between interaction that is initiated by smart objects and interaction initiated by human users, and investigate how an association between interaction partners can take place through explicit human actions as well as invisibly through context information provided by active tags. The concept of invisible preselection of interaction partners based on the user's context is introduced. It enables unobtrusive interaction with smart objects in that it combines different forms of association, e.g. implicit and user initiated association, by transferring interaction stubs to mobile devices based on the user's current situation. Invisible preselection can also be used for remote interaction. By assigning phone numbers to smart objects, we propose making this remote user interaction with everyday items and their virtual counterparts as easy as making a phone call. Mobile phones are also used as mobile infrastructure access points for smart objects. We evaluate the suitability of the proposed concepts on the basis of three concrete examples: a product monitoring system, a smart medicine cabinet, and a remote interaction application.