From three-dimensional (3D) graphics on home video games to the special effects and animation sequences created for feature films, it is apparent that the entertainment industry has emerged as an innovative source of modeling and simulation technology.¹ The U.S. Department of Defense (DOD) has an even longer history of investing in modeling and simulation to support objectives such as training and analysis programs and has supported the development of many of the fundamental computer graphics and networking technologies that underlie both military and entertainment applications of modeling and simulation. Though the two communities differ widely in their structures, incentives, and motivations, opportunities may exist for the entertainment industry and the defense modeling and simulation community to work together to advance the state of the art in modeling and simulation technology. By sharing research results, coordinating research agendas, and working collaboratively when necessary, the entertainment industry and DOD may be able to more efficiently and effectively build a technology base for modeling and simulation that will improve the nation's security and economic performance.²

This report explores the potential for greater cooperation between the entertainment industry and DOD in modeling and simulation. It draws heavily on a workshop convened by the Computer Science and Telecommunications Board of the National Research Council in October 1996 that brought together representatives of the entertainment industry and the defense modeling and simulation community to discuss issues of mutual interest and identify areas for cooperation. The report summarizes major uses of modeling and simulation technology in both defense and entertainment applications, outlines research areas in which the entertainment and defense modeling and simulation communities share a common interest, and identifies other issues that must be addressed to facilitate cooperation and ensure the viability of the technology base for modeling and simulation. It does not explicitly consider the degree to which DOD can adopt commercial off-the-shelf technologies for its own purposes; rather, it examines opportunities for conducting research that could benefit both military and entertainment applications.

As the report demonstrates, the potential exists for greater cooperation between the entertainment industry and DOD, but collaboration may not be easy to achieve. The entertainment industry and DOD have vastly different cultures that reflect different business models, capabilities, and objectives. It is unlikely that the cultures will converge, and bridging them may be difficult. Nevertheless, these differences can be a source of strength. DOD's research efforts and those of the entertainment industry are in many ways complementary rather than contradictory. Whereas DOD's research and development efforts are well funded (by industry standards), meticulously planned, and forward looking, the entertainment industry's efforts are diverse, fast paced, and market oriented. If cultural barriers can be overcome, the resulting cooperation could enable the two communities to leverage each other's strengths to develop a stronger technology base that will allow both to more easily achieve their individual objectives for modeling and simulation.

DOD uses modeling and simulation for a variety of purposes, such as to train individual soldiers, conduct joint training operations, develop doctrine and tactics, formulate operational plans, assess war-fighting situations, evaluate new or upgraded systems, and analyze alternative force structures (see Box 1.1). The technology also supports the requirements of other critical defense needs such as command, control, and communications; computing and software; electronics; manpower, personnel, and training; and manufacturing technology. As a result of this breadth, defense models and simulations range in size and scope from components of large weapons systems through system-level and engagement-level simulations, to simulations of missions and battles, and theater-level campaigns. DOD's Defense Modeling and Simulation Office (DMSO) coordinates military modeling and simulation programs on an interservice level and has played a key role in developing a standard architecture for military simulations. Each of the military services also has a designated office to serve as its single point of contact on all modeling and simulation matters.³

DOD's interest in modeling and simulation is growing. The 1997 Defense Technology Area Plan identifies modeling and simulation as one of five key areas of information technology critical to U.S. defense needs and projects growth in funding for enabling technologies from $169 million in 1998 to $280 million in 2003.⁴ Most of these initiatives will be orchestrated by the DMSO, the Defense Advanced Research Projects Agency (DARPA), the Defense Special Weapons Agency, and the U.S. Army. Several other projects are under way by the Army, Navy, Air Force, and Marines to individually and jointly develop simulation systems. Overall acquisition of training systems by military departments exceeds $1.5 billion per year, including both trainers for specific systems (such as the B-2 bomber) and simulators for the integrated performance of a variety of weapons systems. Development of individual simulation systems can easily cost between $100 million and $1 billion (see Table 1.1).⁵

DOD's growing interest in modeling and simulation derives from several factors. Changes in the geopolitical environment are requiring the military to plan for actions not only in traditional regions of conflict, such as the former Soviet Union and the Middle East, but elsewhere in the world as well. Thus, DOD needs to be able to rapidly model varied locations and scenarios to assist in training troops. In addition, DOD is being asked to conduct a broader range of missions (such as drug interdiction and peacekeeping), to defend against new types of threats, and to coordinate joint operations that cross service and national boundaries. Each of these missions requires the development of new doctrine and tactics as well as training. At the same time, advances in information technology have lowered the cost of computer-based models and simulations, making modeling and simulation a cost-effective alternative to live training. Simulated training exercises do not require the space or transportation needed for a live training exercise, nor do they have the environmental impact of live training exercises.⁶ Already, DOD's modeling and simulation activities, such as SIMNET, have helped the services get away from major field exercises that required the agency to move large numbers of people around. In the future, DOD hopes to use modeling and simulation to provide readily available, operationally valid environments for use by all DOD components. It would like users to have daily access to war-fighting scenarios from their offices, in the same places that they normally work.

DOD has developed a Modeling and Simulation Master Plan as a first step in directing, organizing, and concentrating its modeling and simulation activities. It is intended to be dynamic and flexible, evolving as the technology matures and consensus develops on policy and programmatic issues.

The first objective of the master plan is establishment of a common technical framework to facilitate interoperability among simulations and the reuse of simulation components. The key to this effort is the development of a standard architecture for defense simulations, the High-Level Architecture, with which all defense models and simulations must comply. This architecture was designed to allow DOD to meet its vision of constructing a rapidly configured mix of computer simulations, actual war-fighting systems, and weapons systems simulators geographically distributed and networked, involving tens of thousands of entities to support training, analysis, and acquisition. Such simulations would be used both to train individuals to perform particular tasks, to interpret data, and to make decisions, and to help groups of individuals (tank crews, fighter squadrons) work together as a team.

The second objective of the master plan is to provide timely and authoritative representation of systems (aircraft, ground vehicles, ships, communications systems, etc.), the natural environment (air, space, land, sea, weather, and battle effects), and individual human behaviors.

Efforts are under way to create databases that would allow just-in-time generation of integrated and consistent environmental data to support realistic mission rehearsals anywhere in the world, including locations that are difficult to access or that are operationally dangerous. This work is attempting to develop the capability to generate—with minimal editing—synthetic representations of geographic surfaces that incorporate relevant surface features (trees, rocks, etc.) and to create model-based software tools for feature extraction. Achieving these goals will ensure, for example, that weather fronts that bring rain or snow to an area will affect the transit rate of vehicles and troops and that wind patterns will move trees, create waves, and alter dispersal patterns of smoke and dust. These effects will not only help increase the realism of DOD simulations (and, hence, more realistic training and analysis) but will also allow simulation of different seasonal conditions.

Other objectives include the establishment of a robust infrastructure to meet the needs of simulation developers and end users. The infrastructure will include resource repositories—virtual libraries—and a help desk for users. The goal is to provide common services and tools to simulation developers to further reduce the cost and time required to build high-fidelity representations of real-world systems and processes. Such tools will enable the construction of realistic simulations that interact with actual war-fighting systems to allow combatants to rehearse missions and train as they will fight. It could also facilitate development of virtual prototypes that could be evaluated and perfected with the help of real war fighters before physical realizations are ever constructed. Such virtual prototypes could have applications outside defense, such as in city planning, architecture, and design (see discussion of database generation and manipulation in the "Tools for Creating Simulated Environments" section of Chapter 2).

The final objective of the plan is to share the benefits of modeling and simulation. DOD must educate potential users about the benefits of modeling and simulation. To that end, an extensive study is under way to quantify objective data on the cost-effectiveness and efficiency of modeling and simulation in training, analysis, and acquisition applications throughout DOD. Extensive anecdotal data exist, but no concerted effort has been made to demonstrate the return on investment.

The entertainment industry consists of a varied mix of companies engaged in a broad range of activities, including film, television, radio, recorded music, publishing, performing arts, home entertainment, and video. Companies in these industries are using digital electronic technology for many applications: (1) to deliver existing products, such as video games and video on demand, and potentially to distribute products to audiences that are not reached today; (2) to create electronic games and other forms of digitized material (such as films that have been converted into electronic games); (3) for direct response sales (i.e., home shopping); (4) for new entertainment products that are still in the process of being invented (such as musical books or interactive stories); (5) for location-based entertainment, such as high-tech theme parks based on visual simulation and other offshoots of the aerospace and electronics industries; and (6) for new methods that enhance the quality or lower the costs of producing products (e.g., computer animation systems or virtual reality systems for set design and lighting).⁷

Of these industries, filmmaking, television, video games (including both computer games that run on standard personal computers and console games such as Nintendo, Sega, and Sony systems), and location-based entertainment centers have been most active in adopting modeling and simulation technology. For the most part, these sectors have operated independently of one another, though some blurring of the boundaries is occurring as film studios attempt to develop games based on their movies. Other linkages also exist. Filmmakers and television producers, for instance, often share techniques, technologies, actors, and even content. Companies that produce games are working hand in hand with network service companies to provide networked video games.

These companies play an important role in the U.S. economy. Sales of video games and consoles, such as the Sony PlayStation, Nintendo 64, and Sega Saturn, were expected to surpass $4.3 billion in 1996.⁸ Game boxes themselves accounted for nearly $3.6 billion.⁹ Such devices are attractive to many game players because they sell for roughly $200 compared with $2,000 for a typical personal computer (PC). Nintendo expected to sell out its production of 1 million Ultra 64 machines in 1996, and Sega sales also were expected to reach nearly 1 million. Game boxes themselves do not usually generate significant profits, but they pave the way for sales of game cartridges. Sales of game software for personal computers are also rising and were expected to grow 20 percent in 1996 to $1.2 billion. Part of the increase is the rise in on-line game sites. Though Internet-based games were expected to generate only $90 million in 1996, they are projected to generate $1.6 billion by 2000.¹⁰ The film industry generated another $22 billion in revenues. Box office receipts totaled almost $6 billion in 1996,¹¹ with video tape rentals at $16 billion.¹² These figures do not include revenues from merchandise related to films, such as toys, games, and clothing. Such revenues often exceed box office receipts.

In some areas, modeling and simulation technology has already enabled firms to regain their competitiveness internationally. As Ed Catmull of Pixar Animation Studios noted at the workshop, technology saved the animation industry. Most U.S. animation went overseas in the 1980s as studios looked for ways to cut labor costs. The advent of electronic animation technologies (such as those that made the computer-animated film Toy Story possible), however, has allowed U.S. firms to win back animation; foreign competition is seen as less of a threat to the U.S. industry. In fact, U.S. firms are now raiding other countries for talent.

Technology will continue to transform the entertainment industry in myriad ways, many of which will be unpredictable over the long term. Nevertheless, certain trends are already apparent. Video games are moving onto the Internet, creating a new way to play games and driving changes in the games themselves (see Box 1.2 and Choudhury et al., 1997¹³). A handful of companies are putting the infrastructure in place for game companies like id Software, Spectrum HoloByte, Acclaim, and others to move their games out of their constricted single-player mode into a worldwide, networked, real-time, multiplayer domain. The Total Entertainment Network (TEN), for example, allows subscribers to play on-line versions of Duke Nukem 3D, Quake, Command and Conquer, Warcraft, and Deadlock. More games are added regularly. In its first three months TEN garnered more than 14,000 subscribers who pay $14.95 a month to access its Internet-based games. MPath Interactive, another entrant into the on-line games industry, offers an on-line version of Quake and recently agreed with Hasbro Interactive to put versions of classic Parker Brothers board games, such as Monopoly, Scrabble, and Risk, on line. MPath offers subscribers who have multimedia PCs the ability to talk to other players during games. Players speak into microphones attached to their PCs, and the MPath software digitizes their voices and transmits them over the Internet to other players. Players without microphones can communicate by typing messages.

A growing number of companies are entering the market for location-based entertainment, using virtual reality (VR) technologies as the centerpiece of their centers. Location-based centers generally provide a specific entertainment attraction, often accompanied by a cafe, bar, or restaurant. A recent compilation listed 153 VR entertainment centers worldwide, ranging from restaurants or cafes with one or two VR units to larger facilities and theme parks with up to 40.¹⁴ In some of these centers, participants don a head-mounted display and enter a 3D world through which they navigate with a joystick or ski down a simulated mountain. In others, groups of players sit in pod-like facsimiles of military aircraft and fly through a simulated landscape, engaging enemy targets and communicating with a control tower. Further advances in technology combined with reductions in price could enable simple VR technologies to enter homes. Already, companies such as Thrustmaster Inc. are marketing mock-ups of aircraft cockpits for home use in conjunction with flight simulator games designed for PCs.

Industry analysts, such as John Latta of 4th Wave Inc., see CD-ROMs, "Internetworking," and interactive television as the primary means of delivering entertainment in the 1990s, although motion-based simulators, VR experiences, and large-format films also will contend. With the expansion of infrastructure and content, home entertainment is becoming more popular; spending for in-home entertainment far exceeds that for out-of-home entertainment. The emerging market for 3D PC applications may reinforce this trend.

As the price of 3D image generators continues to decline and performance improves, 3D graphics will become a key feature of home PCs. Latta predicts that by the end of 1998, most new PCs will include 3D graphics accelerators. Some 30 to 40 companies are designing or producing 3D video chips for PCs. The market for 3D accelerators is predicted to grow from 5,200 chips in 1994 to 36 million in 1999. Applications will range from home video and PC games to 3D tools, such as animation and modeling software, VR, multimedia 3D, and interactive television. Venture capitalists have already pumped $200 million into 3D start-up firms, and over 25 companies have invested at least $1 million apiece in multiplayer games, but the market must still be created, and developers have little control over development of the infrastructure.¹⁵

Film companies, too, are pursuing innovations in information technology. Disney's animated feature films have been all digital for several years now and, as demonstrated by Toy Story (produced in association with Pixar Animation Studios), are achieving realistic 3D images. A growing number of nonanimated films, such as Terminator 2: Judgment Day, Jurassic Park, and Casper, incorporate digital effects and characters. Companies such as Boss Film Studios, Digital Domain, and Industrial Light and Magic continue to improve the realism of these effects and are developing ways to digitize real actors for use in stunts and other special effects.¹⁶ In addition, virtually every major Hollywood studio has established a subsidiary to create interactive products, typically computer adventure games based on movies. Record companies, too, seeing the music production innovations being led by specialized multimedia companies, are exploring interactive media. The new Academy of Interactive Arts and Sciences was established to confer awards in the field; the Houston International Film Festival has established new prizes for interactive multimedia products; and the American Film Institute's computer-based graphics, editing, and multimedia classes are overflowing.¹⁷

The idea of linking research efforts in DOD and the entertainment industry is not as far fetched as it might first appear. Connections between the two communities stretch back over the decades and have taken many forms, from sharing products, to sharing technologies, to sharing people.¹⁸ The entertainment industry now rests on a technological foundation laid by large amounts of government-funded research and infrastructure, including advanced computing systems, computer graphics, and the Internet. In the area of computer graphics, for example, early DOD funding resulted in development of the geometry engine, about 1979 (see Box 1.3). This technology has since been incorporated into a number of game devices, such as the new Nintendo 64 machine. Similarly, early advances in networking in the late 1950s and 1960s laid the groundwork for the ARPANET, which grew into today's Internet and has become the foundation of today's growing networked games industry. As these examples demonstrate, 20 years or more often pass before DOD-sponsored research generates new technology that is incorporated into a new product.¹⁹

Technology has also flowed back to DOD. The agency has benefited from the entertainment industry's constant attempts to lower the price/performance ratios for image generation, networking technologies, and content development tools, to name a few areas. It has also benefited from new ideas pioneered by the entertainment industry. The first aircraft simulator created by Edwin Link—which became the basis for the military's flight simulator program—was originally sold to amusement parks as an entertainment device (see position paper by Jacquelyn Ford Morie in Appendix D). Game machines are now being considered for military training.²⁰ Discussed below are several projects currently under way or under consideration to modify commercial hardware and software for military training applications:

• Peter Bonanni, of the Virginia Air National Guard, for example, has been working with Spectrum HoloByte Inc. to modify the Falcon 4.0 flight simulator game for military training. Budgetary pressures and worldwide deployments have caused some segments of the armed forces to face true training shortfalls for the first time in decades. U.S. Air Force active duty and reserve squadrons, for example, have experienced a reduction in training sorties of up to 25 percent as a direct result of deployments in support of contingency operations over Iraq and Bosnia (see position paper by Peter Bonanni in Appendix D). Since conducting realistic training is impossible on most of these missions, simulators provide the only realistic training alternative. Unfortunately, most of the simulators in use today are very expensive, are limited to single-crew training, and are not deployable. As a result, pilots have few opportunities for training while on deployment, and proficiency declines as the deployment wears on. The problem also is occurring in other military services as the trend to use U.S. forces in peace-keeping roles accelerates. Low-cost commercial simulators may be a near-term solution to this military training problem. Though lacking the fidelity to allow fighter pilots to practice certain skills, such as properly timing the release of a weapon to ensure the greatest probability of intercept, low-cost simulators may allow pilots to maintain familiarity with the layout of cockpit and throttle controls and to "keep their heads in the game." According to Peter Bonanni, games such as Falcon 4.0 realistically mimic the look and feel of real military aircraft and allow users to play against computer-generated forces or, in a networked fashion, against other pilots, which facilitates team training opportunities.

• The U.S. Marine Corps has initiated a program to evaluate commercial war games software for use in training. The Marine Corps sees such games as a low-cost way of engaging soldiers in daily decision-making exercises to help improve their tactical decision-making capabilities. The Corps' Combat and Development Command in Quantico, Virginia, evaluated close to 30 games in 1995 for their potential teaching value, examining their cost as well as technical issues such as memory and processor requirements, data accuracy, and ease of use; multiplayer capabilities, level of game play (strategic, operational, or tactical); relevance to the Marine Corps Task Map; and compatibility with Marine Corps doctrine and tactics. In future tests an education specialist will evaluate the educational merits of each game and determine whether it produces negative training. The evaluations to date have found that while no war game was capable of producing a "robust simulated combat environment," several offered potential for training: Harpoon2, Tigers on the Prowl, Operation Crusader, Patriot, and DOOM.²¹ The Computer War Game Assessment Group recommended the use of these games, and the Marine Corps commandant has authorized commanders to permit these games to be loaded onto government computers and to allow Marines to play them during duty hours.²² The Marine Corps has already begun using DOOM for training four-person fire teams. Users play in a networked environment that allows them to cooperate, listen, and make decisions quickly.²³ The game has been modified from its original version to include fighting holes, bunkers, tactical wire, "the fog of war," and friendly fire, as well as Marine Corps weapons, such as the M16(a1) rifle, M-249 squad automatic weapon, and M-67 fragmentation grenades. Such activities are not viewed as a replacement for field training but are used in the hope of making field training more efficient.

• The Army Battle Command Battle Laboratory is discussing the possibility of adapting the Nintendo 64 game machine as a low-cost individual training device. The system, which would be developed by Silicon Graphics Inc. and Paradigm Simulation Inc., would represent an alternative to PCs and CD-ROMs. Initial analyses indicate that the Nintendo 64 is less expensive than alternative trainers and offers more interactivity and visual realism. Unit commanders would be able to purchase them in larger quantities than other systems, allowing more soldiers access.²⁴

• The Marine Corps has awarded a contract to MäK Technologies to design a video game that can be used for military training as well as home entertainment. The company will use the same game engine in both the military and civilian versions. The military version will add more accurate details about tactics and weapons, while the civilian game will be less demanding. Both versions will allow multiple players to compete against each other over a local-area network or the Internet.²⁵

Additional opportunities may exist for DOD and the entertainment industry to share the data and resources used to create simulations. For example, DOD has created a simulation of one of the major tank battles of the Persian Gulf War, 73 Easting. Part of the effort in creating the simulation was collecting geographic data and information regarding the position of military units and terrain features. There are enough similar data readily available to produce comparable studies of Austerlitz, Waterloo, Gettysburg, Antietam, and other battles. Available in formats that permit the viewer to traverse these battlefields in time as well as space, these databases could become staples of history courses, officer training programs, and the countless clubs and societies that cherish military history or stage reenactments. By allowing participants to alter the course of the battles, such simulations could be even more attractive to DOD and the public at large.

To date, the flows of technology between the defense and entertainment industries have been largely uncoordinated. Many derive from large investments the government made in fundamental research and infrastructure for its own purposes but that then became the foundations on which entrepreneurs have created whole new industries. The question that must now be asked is whether there is a way to take advantage of future overlap in interest in a more proactive way to encourage the types of interplay that have occurred in the past.

Military and entertainment simulations have markedly different objectives. In entertainment the driving factor is excitement and fun. Users must want to spend their money to use it again and again (either at home or at an entertainment center) and hopefully are willing to tell others about it. Unrealistically dangerous situations, exaggerated hazardous environments, and multiple lives and heroics are acceptable, even desirable, to increase excitement. Defense simulations, on the other hand, overwhelmingly stress realistic environments and engagement situations. The interactions are serious in nature, can crucially depend on terrain features or other environmental phenomena, and generally rely on the user's ability to coordinate actions with other players.

Nevertheless, many of the future challenges that face the movie industry, games industry, and DOD are similar. A striking example of this is multiplayer simulations using real-time 3D graphics. The DOD is interested in this capability for large-scale training exercises; the games industry is interested in networked games that would allow hundreds or thousands of players to participate. The underlying technologies to support these objectives address similar requirements: networking, low-cost graphics hardware, human modeling, and computer-generated characters. Given future trends in defense modeling and simulation and in the entertainment industry, such overlap is likely to occur more frequently in the future.

These similarities suggest that potential exists for DOD and the entertainment industry to leverage each other's modeling and simulation efforts, provided they understanding the fundamental differences and objectives. Simulation, VR, video games, and film share the common objective of creating a believable artificial world for participants. In this context, believability is less a factor of specific content of the environment than of the perception that a world exists into which participants can port themselves and undertake some actions. In film this process is vicarious; in simulation, VR, and gaming it tends to be active, even allowing participants to choose the form for porting themselves into the environment, whether as occupants of a vehicle moving through the environment, as a separate controllable entity, or as a fully immersed human. Their representation can assume whatever form is appropriate for the environment.

Designing and building such worlds require a common set of enabling technologies, regardless of the application (defense or entertainment) to which the worlds will be put. Because they are fundamental to virtually all simulations, these technologies may represent areas in which DOD and the entertainment industry could collaborate on research and early stages of development:

• Tools for fabricating synthetic environments. Computer-based tools are needed to efficiently create 3D virtual worlds that can be sensed in multiple ways (visual, auditory, tactile, motion, infrared, radar, etc.). Cost rises as the size space, resolution, detail, and dynamic features (objects that can interact with participants, like doors that can open or buildings that can be razed) of the simulated environment increase. Tools for efficiently constructing large complex environments are generally lacking; existing toolsets are quirky and primitive, require substantial training to master, and often prohibit the environment architect from including all of the attributes desired.

• Interfaces. Interfaces provide the portal through which participants interact with a system. They include displays, entry devices such as keyboards or touch-sensitive screens, VR systems, and a host of other input/output devices that link the participant to the simulator. The increase in the richness of the participant's ability to interact with the synthetic environment and other people and agents similarly ported there is especially important as large-scale simulations are constructed.

• Networking technologies. Networking technologies enable large numbers of participants to join in a simulation regardless of their physical locations. The network must be able to accommodate the volume of messages between and among participants in a timely fashion with a minimum amount of delay or latency. These factors are influenced by both the architecture of the network and the protocols for transmitting information. Protocols are needed to minimize message traffic across the network, and service providers need to figure out how they can provide guaranteed levels of service that distinguish between time-critical interactions and lower-priority messages that are less sensitive to time delays.

• Computer-generated forces and autonomous agents. Computer-generated forces and autonomous agents control the actions of elements not directly under the control of a human participant in a simulation. They can be adversaries (as in a computer chess game) or companions (controlling a wingman in a flight simulator) and can represent individual players or aggregated forces (such as an enemy infantry division). Computer-generated forces are critical in any simulation intended to be used by an individual participant or in large networked simulations in which it may not always be possible to ensure enough players to control all the necessary entities.²⁶ Such forces typically strive to display behaviors characteristic of intelligent human participants.

Both DOD and the entertainment industry could benefit from greater collaboration in the above technical areas. The primary benefit of such collaboration would be the development of a technology base that could support modeling and simulation efforts in either defense or entertainment, eliminating redundancies and sharing technical advances. Collaboration could improve the competitive advantage of entertainment companies and the ability of DOD to meet its national security objectives more efficiently than if the two communities continued to operate independently. As Ed Catmull, of Pixar Animation Studios, and Eric Haseltine, of Walt Disney Imagineering, noted, funding from defense agencies such as DARPA had a significant effect on the development of fundamental technologies critical to defense and entertainment; moreover, it helped develop the human resources required to research, develop, and advance those technologies. More formal collaboration may give DOD and the entertainment industry more opportunities to gain greater leverage from each other's research investments to further their own objectives. Such collaboration will become especially important given continued constraints on defense research and development (R&D) spending. Between 1987 and 1996, real DOD expenditures for R&D declined 27 percent, though the largest cuts were allocated to the development portion of the budget; expenditures on basic and applied research remained almost level. Given current attempts to balance the federal budget and realign federal expenditures on defense R&D to reflect a new set of national priorities, it is unlikely that defense R&D budgets will rise significantly in the near future.

Achieving these benefits will require efforts in two areas. First, DOD and the entertainment industry must identify research areas in which they have a common interest. This is something of an exercise in which the two communities plot their research agendas, identify areas of commonality, and determine ways in which the capabilities of each community can best be leveraged to move the field forward. Second, they must find ways to facilitate collaboration between the two research communities. Differences in culture and business practices must be overcome, and mechanisms must be put in place to facilitate information sharing and, perhaps, collaborative research projects. Unless these types of obstacles are overcome, even the best intentions will not produce fruitful results.

26. DOD's experimentation with distributed interactive simulations during the late 1980s resulted in constant pressure to increase the number of participants in simulated exercises. Because there were not enough simulators or participants to populate a typical battlefield scenario (nor did the technical capability exist to efficiently network together large numbers of participants), DOD began to rely on the use of computer-generated forces.