Huseby Zoom Maps: A Design Methodology for Tactile Graphics

Abstract

Zoom Maps are a recent design development from the Teaching Aides Department at Huseby Resource Centre for the Visually Impaired Oslo, Norway (see Figures 1 and 2). The aim of Zoom graphics is to produce better maps for individuals with visual impairments and to present a design methodology for the producers of tactile graphics. The first two pilot tests of a set of Zoom Maps have proved favorable (see the Pilot tests section). [FIGURE 1 OMITTED] Zoom Maps and Zoom graphics were designed specifically for braille readers who are not accustomed to reading tactile graphics. Zoom Maps can be thought of as introductory maps that a reader with visual impairment uses before he or she advances to more complicated maps. A series of Zoom Maps can be compared to those created by online map services. In an online map, a map of an area is presented from a distance and the user is able to closer and closer to see more and more details, both geographical and political. Instead of online screen images, however, Zoom Maps provide hardcopy tactile maps which each new close-up results a new, more detailed, page of a tactile graphic (see Figure 3). In Zoom Maps, the amount of graphic information is restricted to avoid clutter. If the graphics exceed a given amount, the original graphic is divided to create a new map with fewer graphics and more specific information. This division can result a series or hierarchy of maps that take a small section of a map and zoom in on it--hence the name, Zoom Maps. [FIGURE 2 OMITTED] MAP HIERARCHY The map hierarchy and number of maps that are needed are dependent on which geographic information will be presented. That is, if one wants to show towns all the counties of a region, then it is likely that more maps will be required than if only select towns of that region are to be shown. If there is a large amount of information a section of a map, the section needs to be divided into segments--such as Northwest, Northeast, Southeast, and Southwest--and then four new maps are created to show the detailed information for each new section (see Figure 3). [FIGURE 3 OMITTED] DESIGN The design of the maps is based on four main concepts or rules. The first rule is to use the structured reading methods of a braille reader, that is, to read a text page line for line. The second rule is to divide text from graphics by a defining rectangle. The third rule is to restrict the amount of symbolic graphic information that is allowed one tactile graphic. The fourth rule is to use texture to create contrast between the textures used to differentiate geographic areas. One result of these rules is that each new map will, for the reader, seem familiar to the ones from before and thereby establish consistency. Another result is that they give the designer clearer guidelines for creating certain tactile graphics. Structured reading A reader of braille first scans the page and then reads one line after another. Zoom Maps take this process into consideration by placing text used a map an orderly way, similar to a page of braille. Text is placed only at the sides of the defining rectangle. Division of text and graphics Graphics and text appear on the same page of a Zoom Map, but they are physically divided by a rectangle. The graphics of the map are encompassed by a rectangle, and the text of the map is on the outside of the rectangle. The text on the outside of the rectangle is adjacent to the specific part of the graphic that it relates to. If there is a great distance between the text and the graphic, a leading line (made up of the braille letter g), is used to connect the text to the graphic. The purpose of using the letter g is to differentiate clearly between a leading line and a line used the graphic. By doing so, the leading line is less likely to be confused with a graphic line and therefore does not add graphic clutter to the map. …