Information spaces, information access environments designed explicitly for user navigation, can provide an ideal environment to support information access tasks. By providing cues for orientation, the learner will always be aware of where he is in the material (how much have I seen? how much more to go?). By designing explicitly for navigation, the user will always know which path he is on, what choices are available at a junction, and where they lead. And, by virtue of the commitment to a spatial metaphor, a map of the information space can be created. This map serves both as a wayfinding aid during navigation, and as a way of concisely communicating the both the content and the organizing principles of the space in a pictorial way.
We want our information spaces to support useful information access tasks. So, the question now turns from theory - the desirable properties of navigable information spaces in general - to design - how one takes an idea, a collection of objects, or a mass of knowledge, and creates a concrete, useable artifact that serves the task and has these properties.
Many approaches are possible to this design problem. The fortunate situation in this case is that there are a large number of information spaces that confront and solve it well: educational museum exhibits. By this, we mean the kinds of exhibits found in science museums, natural history museums, or other kinds of museums, perhaps dedicated to a specific purpose, event, or idea. These exhibits take a set of physical, tangible objects and arrange them in space, presenting and annotating them appropriately to inform, entertain, and teach the viewer. They are environments that communicate, physical spaces created to faciliate a learning experience for the visitor. Effective educational exhibits are also information spaces in every sense outlined here. By virtue of their existence in the physical environment, they should provide sufficient orientation cues to prevent a feeling of being lost. Some exhibits use basic architectural elements such as hallways, rooms, and doorways to create a well-defined circulation path; others allow freer movement. All effective exhibits, however, are constructed on organizing principles that give meaning to navigation in the space. And every exhibit studied uses some kind of map, either on a brochure distributed to viewers, displayed in the exhibit itself, or, most often, both. Educational museum exhibits are physical exemplars of information spaces that communicate knowledge and in many ways represent the ideal of an environment for doing so. They are immersive, interactive, and engaging, and they focus the entire attention of the visitor on the experience. Successful exhibits can make that experience memorable in ways that other media cannot.
We would like our information spaces to approach this physical ideal. But there remains an enormous gap between the raw electronic material and a finished product. For educational exhibits, in this gap stands a group of individuals - curators, exhibit designers, exhibit planners, graphic designers, and others - who are responsible for organizing, annotating, and presenting the materials that make up the exhibit.
Exhibit planners and designers, however, must deal with a very different set of constraints than one who would design an information space in a digital medium. They begin with a collection of (often) unique artifacts, which cannot be modified or duplicated. Materials, unlike pixels, have an associated cost, and the entire exhibit is mounted in a physically located space with fixed dimensions. The designers must accomodate the viewers' needs for personal space and room for comfortable circulation. And, of course, the exhibit must comply with the laws of physics!
Each of those considerations depends particularly on the medium of presentation, and how it is experienced as a physical space by its viewers. If we claim that these exhibits have interesting things to say about how we might create digital information spaces, we must isolate the aspects of design and interaction that would be applicable in both physical and digital media. Two such aspects of exhibits are:
By focusing on how exhibits succeed in meeting those two requirements, we can use the design principles they were based on to make statements about how we might design digital information spaces. These two aspects of exhibit spaces, and the fact that we intend to implement digital information spaces, recommend a top-level division on those principles:
A design principle is a way to design an artifact to meet a requirement. A design principle for an electrical engineer might be ``to reduce noise in a circuit, use a low-pass filter.'' It doesn't specify a particular circuit, or what kind of low-pass filter might be best. Its utility arises from its ability to help solve a wide class of problems, and in how it can be applied successfully in specific situations. So, how we will generalize what we learn from exhibits is to enumerate a collection of design principles that can be applied to information spaces.
What makes for a good design principle? A few properties of good design principles are:
These properties suggest a general schema for presenting a design principle:
This schema will be the outline for the presentation of the principles to follow. How these principles were arrived at, however, begins with the study of exemplary, physical information spaces: the educational exhibits.
For each of the exhibits studied, there were two main sources of evidence: observation and mapping of the exhibit space and the items contained within, and interviews with the designers and developers of the exhibit. The exhibits were studied and mapped before the interviews to provide starting points for discussion.
Observation of the space proceeded by documenting of the location and describing of the items in the exhibit. For some exhibits, floor plans showing the content of the exhibit were not available from developers or designers. In this case, brochures distributed to the public which had a map of the exhibit were obtained and annotated with relevant features as the exhibit was traversed.
Noted features included:
Significant environmental features of the exhibit space, such as wall treatments, carpeting, decorative motifs, and lighting were noted. Any brochures or printed matter distributed to the public was collected, and photographs of the exhibit space were taken when permitted.
After the exhibit was studied and mapped, interviews were conducted with some of those responsible for developing, designing, and maintaining the exhibit. Mounting an exhibit is an enterprise that requires the concerted effort of many individuals, but the focus was on those reponsible for the two aspects of exhibits mentioned before: exhibits as spatial organizations of information and exhibits as navigable spaces.
The precise roles played by individuals on an exhibit's design team and how they impacted those two aspects of exhibits varied with each organizational circumstance. Among those interviewed, however, some common terms were used to describe certain roles in exhibit development. They included:
Of course, many others participate in the development process, such as graphic designers, content specialists, and educational or learning specialists.
Interviews were conducted in person or by telephone, beginning from a set of questions and topics outlined in Appendix C. The interviews did not proceed in a strict, question-answer format, but concentrated on topics that were most pertinent to the features of the particular exhibit and the role that individual played in its development.
The rest of this chapter contains plan maps of the exhibits, walk-throughs noting important features, and background on those interviewed from the design teams for the exhibits.
Leonardo da Vinci: Scientist, Inventor, Artist, was a temporary exhibit open from March 3 to September 4, 1997, at the Museum of Science in Boston, Massachusetts. Leonardo da Vinci was a Italian Renaissance scientist, inventor, and artist. His creative genius incomparably influenced Western art, his restless imagination envisioned flying machines centuries before their time, and his investigations into the human body produced the most accurate anatomical sketches to date.
The 1,400 m2 (15,000 square foot) exhibit featured both original and reproduced sketches, notebooks, and manuscripts by Leonardo. It also had hands-on activities, models of his inventions, and original paintings and sketches by his contemporaries. Computer workstations and kiosks 1 scattered throughout the exhibit allowed visitors to explore multimedia CD-ROMs of Leonardo's manuscripts.
Referring to the map from the exhibit guide (Figure 3-1), the detailed floor plan (Figures 3-2, 3-3, and 3-4), and the exhibit catalog (Appendix A), we see that the viewer begins in the Object Theater. It has a ten minute presentation of three-dimensional objects, special effects, and video to introduce Leonardo's life and times. Then, he proceeds to the first section of the exhibit, entitled ``Who was Leonardo?'' It is divided into two rooms, ``Introduction to the Renaissance'' and ``Florence in 1470,'' which together provide historical context (marked 2 on the plan in Figure 3-2), offer sketches from Leonardo's early career (6-13), and present labels describing the three main activities Leonardo engaged in throughout his life (3): scientific observation, invention, and artistic expression.
From there, the viewer could turn right into the two Art Studio rooms, or proceed on to the Art Gallery. These three rooms formed the next major section, ``The Natural Artist.'' In the first Art Studio room, three artistic techniques Leonardo used, chiaoscuro (the realistic rendering of depth using light and shadow), perspective projection, and sfumato (the use of ``smoke'' or shading to suggest movement), are described on labels (21, 25, 27, 29), and exemplified in sketches by Leonardo (22, 24, 28) and a reproduction of the Mona Lisa (28). Hands-on activities encourage the visitor to draw in perspective (23) or to sketch a draped figure (26).
In the second Art Studio room, Leonardo's participation in the studio of the Florentine artist Verocchio is related. A wall-sized mural (41) shows what activities might have taken place in Verocchio's workshop: drawing, painting, sculpting, and casting, all at the same time. It also has a contemporary's sketch of the Last Supper and studies for a lost mural, the Battle of Anghiari. As the viewer moves into the Art Gallery, a free-standing easel with label text (45) describes his early years as an artist in Florence. The Art Gallery itself contains sketches and paintings by Leonardo, his contemporaries, and his followers.
The next section, ``The Restless Inventor,'' has numerous sketches of inventions and engineering projects Leonardo proposed. The contents are spatially divided among the subjects of military machines, architecture, hydraulics, clocks, machinery, and flight. Hands-on activities in the center of the space illustrate the principles of hydraulics, arch-building, and flight (150, 162, 170, 171, 172, 178, and 179) and are interspersed with working models based on his sketches and notes. This area is introduced by a large free-standing label (183), ``The Middle Years,'' which identifies this section with the period 1482-1506, when he was employed both in Milan and Florence.
The final section of works, ``The Solitary Scientist,'' has two rooms with his anatomical sketches and a strange series of drawings of cataclysmic floods (195-202). The section has labels (197, 205) that identify these works with his later years (1507-1519).
The last part of the exhibit has a legacy area that describes the influence of Leonardo's works on later artists, scientists, and inventors. Labels reiterate the three aspects of Leonardo's diverse genius (221, 222, 226, 227, 230), and a resource room with books and multimedia workstations lets the viewer explore further into Leonardo's works and thoughts. In addition to these ways of relating his legacy, a play staged hourly illustrates it dramatically. Finally, as the viewer exits the exhibit, he passes a table with feedback cards and sample responses.
Interviews took place with three individuals from the Leonardo design team. The first was with Mr. Lynotoyos, the exhibit designer [Lynotoyos, 1997] for Leonardo, the second with Edward Rodley, the exhibit planner for the exhibit [Rodley, 1997], and the third with Judy Rand, an exhibit consultant who advised the editing of the label text for the exhibit [Rand, 1997b].
The John F. Kennedy Museum, located in the John F. Kennedy Library in Boston, Massachusetts, is devoted to the life and family of the thirty-fifth President of the United States. Originally opened with the Library on October 20, 1979, the museum was redeveloped and rededicated in 1993. The 1,700 m2 (18,000 square foot) museum is comprised of an 18 minute introductory film and twenty one exhibits arranged in the main museum space, which exits onto a glass pavilion overlooking the Boston Harbor. Figure 3-5 is a map from the exhibit brochure, and Figures 3-6 and 3-7 are a floor plan of the exhibits. A catalog of their contents is in Appendix B.
The introductory film covers Kennedy's youth, wartime service, and early political career, ending at the 1960 Democratic National Convention. After the visitor exits the theater, he enters the first set of exhibits (marked 1 through 6 on the map), which illustrate the successful Kennedy campaign for President: his capture of the Democratic nomination (1-3), victory in the election against Richard Nixon (4-5), and his inaugural address (6). This first section of the museum, in particular exhibits 1-5, evoke an atmosphere of the campaign trail (``Main Street, USA'' in 1960) with faux brick wall treatments, storefronts with period appliances and memorabilia, and a re-created campaign office. Monitors with video footage of campaign commercials and debates (catalog items M1-M62), Walter Cronkite announcing election results (M19), and President Kennedy's inaugural address (M7) are also located here.
After passing the Presidential Seal, between Presidential and United States Flags (O9A and 09B), the visitor continues to a series of exhibits chronicling Kennedy's Presidency (7-15). The main hallway (7) is lined with cases of gifts from heads of state (O10, O11, and O12), and various photographs of Kennedy at the White House.
Exhibits branching off to each side of this hallway touch on a particular program or event in his administration. Exhibit 8 describes his Cabinet; 9, domestic and international affairs, featuring clips of a press conference (M8); 10, the Peace Corps; 11, the Cuban missile crisis, in a 17-minute documentary film (M10); and 12, the space program. The hallway is decorated in a manner reminiscent of the White House interior, with plush red carpets and wall colors chosen to match those of rooms in the White House at the time.
At the end of the corridor is a rotating exhibit (13). At the time of this survey, it had documents and photographs from a state dinner held in honor of Grand Duchess Caroline and Prince Jean of Luxembourg. A large, octagonal glass case situated in the center of the room contained the dress Jacqueline Kennedy wore that evening.
Turning right, an exhibit entitled ``The Office of the Attorney General'' presents the role and contributions of President Kennedy's brother, Robert F. Kennedy, during his tenure in the Kennedy Administration (14). Exhibit 15 recreates the Oval Office, with replicas of his desk and favorite rocking chair. Two videos play footage of important speeches during his Presidency, one on integration at the University of Alabama and the other on the Nuclear Test Ban Treaty.
Past the Oval Office, the remaining exhibits turn to the private side of the Kennedy family. Exhibit 16 contains photographs and memorabilia about the life and accomplishments of the First Lady, Jacqueline Bouvier Kennedy, while 17 traces the roots of the Kennedy family from Ireland to Boston (and back: President Kennedy returned to Ireland in 1963 on a state visit). Exhibit 18 shows how mental retardation was brought to public attention by the Kennedy family, and their influence on reforming public policy in this area.
Exhibit 19 is a darkened corridor with four monitors (M18) playing news footage of Walter Cronkite reporting John F. Kennedy's assassination. The visitor moves from there to a circular area with photographs of memorials to him around the world (O22) and then to a legacy exhibit (20), which illustrates the lasting accomplishments and influence of the Kennedy family. The exhibit exits onto a large pavilion overlooking the Boston Harbor where the visitor can reflect on what he has seen.
Interviews were conducted with Frank Rigg, Curator of Exhibits and Collections at the Museum [Rigg, 1998], and Jim Wagner, Curatorial Assistant [Rigg and Wagner, 1997].
This exhibit is located at the National Air and Space Museum, one of the museums of the Smithsonian Institution in Washington, D.C. It shows how the space programs of the United States and the Soviet Union began in competition, but later cooperated to achieve a permanent presence in space. It features original and scale models of space vehicles, rockets and missiles, reconaissance satellites, and space suits, along with technical specifications, historical material, and video footage. Figure 3-8 contains a floor plan of the exhibit.
It is situated in a multi-story, 930 m2(10,000 square foot) main space, with a 200 m2(2,300 square foot) adjoining space housing the Apollo lunar landing module. The exhibit is arranged as an open plan - the visitor, after entering from the main museum hallway at the bottom of the floor plan, is free to wander with few constraints on his movement.
The walkthrough will proceed roughly counterclockwise from the reconstructed V-2 ballistic missile at the bottom of the floor plan. From there, the visitor moves past the large, octagonal pit containing originals and replicas of military missiles and rockets. Visitors can descend stairs into the bottom of the pit to obtain a close-up view of the missiles and rockets. Labels arranged around the pit outline the origin of the space race as a quest for military supremacy in space.
Moving to the wall on the right side of the floor plan, the first set of labels, marked ``The Race Begins,'' describe how the race for space exploration began with the launching of the Sputnik satellite by the Soviet Union in 1957. Moving around the corner, further material relates how the next race was to send a man into space, a race the Soviets won with Yuri Gagarin's Earth orbit on April 24, 1961.
The next set of exhibits concerns the final milestone in the race for space exploration, that of sending a man to the moon and back again. Soviet and American lunar suits are featured, along with a label describing how the race ended on July 20, 1969 with the success of the Apollo 11 mission. Overhead, Soyuz and Apollo orbiters are docked together as they were in the Apollo-Soyuz Test Project, the first cooperative space mission between the United States and the Soviet Union. Also worth noting is a timeline mounted on the right wall above these exhibits, proceeding forward from 1957, the launching of Sputnik, to 1975, the date of the Apollo-Soyuz Test Project.
Turning left along the wall at the top of the plan, the exhbit traces the development of reconaissance satellites. Original Soviet and American satellites are featured, along with video footage of the Americans' surprising film recovery technique - literally snagging a parachuting film capsule out of the air with a passing aircraft.
Past the reconaissance section are exhibits on Russian and American space stations, the 1994 Shuttle-MIR missions, the proposed International Space Station, and astronauts' life in space stations. A test version (to scale) of the Hubble Space Telescope, a scale model of the Space Shuttle, and Skylab occupy the remainder of the main exhibit space. The adjoining space is occupied by the Apollo lunar landing module.
The photographs in Figure 3-9 can give a better idea of the scale of the objects in this exhibit. The first photograph looks down from a balcony over the exhibit floor towards Skylab in the background. A V-2 replica is visible in the left foreground, and missiles rising from the octagonal pit are in the right foreground. The second was taken from the exhibit floor, looking towards the Apollo-Soyuz modules past the missile pit.
The designer of The Space Race, William Jacobs at the National Air and Space Museum, was interviewed [Jacobs, 1998].
Where Next, Columbus? is an exhibit also located in the National Air and Space Museum. A floor plan of the exhibit is found in Figure 3-10. It encourages the viewer to consider the future of space exploration, and speculates on future destinations for human and robotic explorers and the technologies that would take them there. The 950 m2 (10,000 square foot) space is divided into five main sections.
Passing through the entrance at the lower right of the floor plan, the visitor encounters the first section, ``Exploring This World.'' It briefly chronicles the history of European exploration of the New World, American exploration of the West, and the United States space program's successful manned mission to the Moon (see Figure 3-11).
The next section, ``Challenges for Space Explorers,'' explores some of the dangers and issues facing humans when they venture into space. These include the risks posed by meteoroids and radiation, ways to stay physically fit in a near-zero-gravity environment, and the tradeoffs among propulsion technologies in space.
The third section, ``Exploring New Worlds in Space,'' asks how we might go about exploring our nearest planetary neighbor, Mars. Some of the requirements of both a manned and unmanned mission are illustrated, and the possible role of autonomous robots on an interplanetary mission is explored. This part of this exhibit is situated in an environment that realistically simulates the surface of Mars (Figure 3-12).
Farther on, the room marked ``Habitat'' speculates on some of the means humans might use to survive permanently in outer space, such as hydroponic agriculture. A theater across the corridor screens a rotation of films on space exploration.
The final section of the exhibit, ``To The Stars,'' asks if there are other worlds with intelligent beings beyond our solar system. This section describes the Search for Extraterrestial Intelligence (SETI) Project and has replicas of the plaques representing humankind to those who might recover the interplanetary satellites Pioneer and Voyager. A stellarium, showing the stars of the Milky Way as tiny points of light suspended in space, shows just how little of the universe we have managed to explore to date. The exhibit ends with an interactive survey that asks the visitor's opinions on space exploration and what resources should be dedicated to it.
William Jacobs also designed this exhibit, and it was discussed in the interview mentioned earlier.
Several other exhibits were also studied, and are more briefly described below.
This museum, dedicated to preserving the memory of the Holocaust and its victims, is located in Washington, D.C. It includes a three-floor Permanent Exhibit that chronicles the rise of the Nazi regime and anti-Semitism in Germany, the Final Solution and the Nazi death camps, resistance to the Nazis, and the camps' liberation.
Visitors begin with a 23 minute introductory film that explains the Museum's history and purpose and the significance of some of the architectural features in the museum. They are then directed to an elevator that takes them up to the fourth floor of the permanent exhibit, from which they descend to the Hall of Remembrance on the second floor. Maps from the exhibit brochure are in Figure 3-13.
Linda Melone, the Museum Specialist for Public Services, was interviewed [Melone, 1998].
This small exhibit, located in the National Museum of Natural History in Washington, D.C., educates the visitor about marine ecosystems: what they are, their importance to the global environment, how humans impact them, and how scientists study them. It compares two living models of marine ecosystems (the Maine rocky shore and a Carribean coral reef), illustrates the components of a marine ecosystem, and shows how humans can both preserve and destroy these environments. Bryan Seiling, the exhibit designer for Exploring Marine Ecosystems, was interviewed [Seiling, 1998]. Photographs from the exhibit are in Figure 3-14.
This exhibit, also at the National Museum of National History, showcases the Museum's collection of plant and animal fossils. The multi-level exhibit is roughly divided into sections presenting fossils of marine creatures, dinosaurs, mammals, and plants. Photographs from the exhibit are in Figure 3-15.
In the study of these exhibits and how they were designed common patterns emerge in the problem-solving process of creating these spatial information designs. We hope to capture these patterns in our design principles. By considering the two aspects of exhibits mentioned before - the spatial organization of information and navigability - we will be able to apply those principles to design digital information spaces.
These exhibits are not our only source of principles. We will also cite the established literature on exhibit development and design, as well as research in environmental cognition that indicates what kinds of physical spaces are effectively navigable. When a principle is exemplified in an actual exhibit, however, it gains immediacy, relevance, and additional validity.