The GIS WallBoard

The design of today's geographic information systems (GISs) is limited by the physical size of computer displays, which are usually somewhere between 10 and 24 inches. This small display size requires objects to be shown in miniature and often restricts usage to a single person. Exceptions to this setting are recent considerations of Virtual Worlds, in which users get the impression of living in the same space as that which they are manipulating (Jacobson 1995) by wearing head gear in front of their eyes. An alternative is also envisioned with the advent of new hardware technology featuring large-scale displays (Elrod et al. 1992), which may take up the size of an entire wall (Negroponte 1995)--three by five meters or more. Interactions with spatial data on such devices may provide users with new spatial experiences and enable improved collaboration among users.

This paper explores what a GIS would be like if a wall-sized version were available. Such an environment would be useful for many applications, such as for planners attempting to deal with complex planning requirements for say, an urban renewal scheme, or for electric utility managers who currently rely on huge paper maps mounted on walls. It introduces the concept of a GIS wall device, referred to as the WallBoard, which allows multiple users to view and interact with a large-scale, touch-sensitive display. The WallBoard is the organizing metaphor for wall-sized GIS devices, much like the desktop is for office applications running on personal computers (Smith et al. 1982).

Unlike smaller-scaled devices where a user performs all interactions from more or less the same position and perspective, the WallBoard supports multiple spatial perspectives and experiences. Zubin's (1989) categorization of how humans perceive objects in the physical world includes small objects that can be perceived from a single perspective; objects that are too large to be manipulated with human hands and require scanning with the eyes; and larger objects that need walking through and multiple perspectives in order to be perceived. With current GIS technology, users are only exposed to the first type of experience. The large-scale display of the WallBoard, however, changes how users perceive and interact with spatial information. Where representations of geographic objects, such as buildings or forests, on desktop GISs could be manipulated by human hands and perceived at a single glance, representations of these same geographic objects on the WallBoard may be too large to be perceived from a single perspective and, therefore, require scanning back and forth. In fact, users may now have to step away from the WallBoard to see the big picture. Such experiences may be critical to evaluate correctly a model.

With the guiding principle being ease of use, we endow the WallBoard with a good measure of intelligence. It is assumed that the WallBoard has full multimedia capabilities including sound, graphics, and animation. It also has all the necessary sensors to accommodate multi-modal inputs from gestures, eye-contact, and voice. This may sound fiction today, but work in progress at research labs (Elrod et al. 1992; Cassell et al. 1994) indicates that such a scenario is not so far away.

This paper continues with a brief analysis of how the WallBoard contributes to collaborative spatial decision-making and presents two sample scenarios utilizing the WallBoard. Section 3 describes the design of the WallBoard and Section 4 investigates multi-modal interactions with the WallBoard. The degree to which certain interaction modalities are either possible or not at different ranges from the WallBoard, leads to a categorization of three interaction spaces. Section 6 studies GIS interactions--selections, zoom, pan, rotation, navigation--if the user is within an arm's length from the WallBoard. The paper concludes with a discussion of future research.

Last updated on January 31, 1996.