The Digital Playing Desk: a Case Study for Augmented Reality

To compare the advantages and disadvantages of a "Natural User Interface" (see Rauterberg & Steiger 1996) a field study was carried out. During five days of the largest computer fair in Switzerland four different computer stations with (1) a command language, (2) a mouse, (3) a touch screen, and (4) a Digital Playing Desk (DPD) interface was presented for public use. In this version of the DPD the user has to play a board game by moving a real chip on a virtual playing field against a virtual player. The task was to win the computer game "Go-bang". The reactions of the virtual player were simulated by "emoticons" as colored comic strip pictures with a corresponding sound pattern. We investigated the effects of these four different interaction techniques with two different methods: (a) an inquiry with a questionnaire, and (b) a field test for public and anonymous use. (a) Results of the inquiry: 304 visitors rated the usability of all four stations on a bipolar scale. The touch screen station was rated as the easiest to use interaction technique, followed by the mouse and DPD interface; the "tail-light" was the command language interface. One very important result was a significant correlation between "age" and "DPD usability". This correlation means that older people prefer significantly more a graspable user interface in form of the DPD than younger people. (b) Results of the field test: The analysis of 9'006 automatically recorded contacts to one of the four stations shows that the highest chance to win the game could be observed for the DPD interface technique. We conclude that the DPD as a graspable user interface with emotional, nonverbal feedback is a promising candidate for the next generation of dialog techniques.