Integrating user models into device prototype design

The interaction between humans and machines is ubiquitous in daily life. Some interaction techniques are more efficient or effective than others for certain tasks or users. During the development of new systems, the user is referred frequently too late into the development process. This is due to the fact that a prototype does not exist to verify the system by the user. This article outlines some ideas regarding the relationship between the systems specification and the user requirements at this early stage of the design process through the use of an appropriate specification tool. This tool has been developed by the Department of Technical Computer Science that enables the designer to create models of tasks, users and devices and to connect these models to visualise the relations between them. Additionally the mode of operation of the developed tool is represented on the basis of a suitable example