BOX 6.2
Vehicle Navigation Systems in the United States

Becoming “lost” implies disorientation, a consequence of the failure to recognize one’s current location, the failure to recognize local or distant landmarks, the failure to understand (or interpret) local signage, the inability to retrace the current path, the breakdown of cognitive processing (such as path integration or ability to define a homing vector), and the resultant emotional stress.

Not only do some drivers in the United States get lost when departing from a habitual travel route, but they cannot recover from the error. They have not developed the spatial thinking skills (including map reading) to be able to recover positional and orientational information from memory or from examining their proximate environment. Obviously this situation is not universal, and many highly skilled wayfinders and navigators are also present in the general population. However, a thriving technology, in-vehicle navigation systems (IVNS), has been developed to

  • aid those who are lost directly by telling them where they are and giving directions in a spatialized natural language suitable for interpretation by spatially naive or unskilled travelers (e.g., the General Motors Onstar System) or

  • provide in-vehicle visual or verbal instructions about a route to be traveled (e.g., screen-based road maps or verbal descriptions of routes).

Drivers have the luxury of choosing to be a navigator or a wayfinder. To navigate implies following a pre-planned route without departure except for unexpected emergencies (e.g., congestion, accidents, construction.). Wayfinding involves searching out a path rather than exactly following a pre-planned route. In the former case, the navigator has to recognize the presence of defined choice points where actions such as changing direction are involved. It is often referred to as “piloting,” where the driver proceeds from landmark to landmark in a prescribed sequence. Wayfinders often choose their own routes, incorporating local knowledge of road systems plus select path segments by using their spatial skills (e.g., general orientational, directional, and distance knowledge or knowledge of environmental layout and its geometry). Strategies such as shortcutting through familiar or unfamiliar areas can be incorporated into the wayfinding strategy on both the outward and return journey.

Research on human navigation and wayfinding indicates that females often prefer the “piloting” system for local navigation, using a landmark to landmark (or choice point to choice point) decision support system. Males prefer to use their understanding of the geometry of layouts as a primary support system, enabling tactics such as shortcutting and minimizing travel time or travel distance (described as a “homing vector” or “path integration” procedure) (Montello et al., 1999; Saucier et al., 2002). The in-vehicle support system to accommodate this activity can be visual (map based), minimally verbally descriptive, or reliant only on a simple device such as a dashboard compass (Battista, 1990; Beatty and Tröster, 1987; Ferguson and Hegarty, 1993; Lawton, 1994; Loomis et. al., 1999; O’Laughlin and Brubaker, 1998).

In-vehicle navigation support systems can be low tech in design: a dashboard compass, a handheld cartographic road map (e.g., topographic sheet), or a simplified and linearized route map (as in an AAA Trip-Tik). Because the bulk of daily travel is regularly episodic and habitual, relying on people’s cognitive maps (or environmental knowledge stored in long-term memory), drivers in most situations have little need for an in-vehicle navigation support system. Exceptions occur when (1) a well-known route is obstructed, requiring a change of travel plans to bypass the obstruction; (2) one is required to travel to an unfamiliar destination; (3) one is exploring new places for, say, recreational or aesthetic purposes; and (4) one has become lost. In most of these cases, a low-tech system can be replaced by (or supplemented with) a high-tech IVNS.

of the nature of the data, the ways of thinking, and the problems characteristic of the field within which the system could be used. They develop a working understanding of the tool—especially its glitches and quirks—as they use it. In using systems for calculating, for example, they appreciate the difference between truncating and rounding, the necessity for appreciating the number of significant digits, the differences in the effects of error on addition and subtraction versus multipli-



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