We explore techniques from visualization and computational geometry to make tactical information more intuitive to a military commander. To be successful, the commander must quickly grasp, and react to, changes in the evolving battle. Thus the commander must possess good situation awareness (SA).A particular problem is to reduce the information complexity entailed by understanding the positional and evolutionary potential of the many individual entities (micro states), each with its own organizational allegiance, capabilities, and attributes. The challenge is to combine the many individual microstates into a few integrated macrostates and then display this information to the commander in a way that is instantly meaningful. To improve the acquisition of SA, we apply principles of human visual perception. In particular, we exploit the organizational properties of gestalt figures and the phenomenon of global preference to create displays that allow the commander to quickly find and integrate relevant information on the location, identity, and concentration of friendly and enemy units.We postulate that an appropriate technical translation of this psychological concept is to consider the spatial arrangement of the units as a geometric density assignment problem, based, to the first order, on geometric proximity. The resulting density and clustering of units is represented using color. To further enhance the ability to grasp the evolving dynamics of an engagement, we compress the data into a short temporal sequence of images. For example, several days of maneuver may be compressed into a motion sequence of a few minutes. We report preliminary findings focusing on the computational geometry aspects, and on the visualization requirements.

Military commanders must understand the complexities ofthe tactical picture, which is made up ofmany individual entities (microstates) with their own organizational allegiance, capabilities, and attributes. Further, while individual events can occur quickly, a battle can occupy several hours to days. It is inadequate to simply perceive the differentiated data about battlefield entities at some point in time-the commander must understand the integrated meaning of the entities as they interact across time. We say that the commander is building situation awareness (SA), and doing so using traditional information displays consumes scarce resources of time and cognitive effort. The challenge is to combine the many individual microstates into a few integrated macrostates and display this information to the commander in a way that is instantly meaningful. We suggest a method for reducing the time and cognitive effort necessary to acquire SA by applying principles of visual perception to the design ofbaulefield visualization displays. Specifically, we exploit the organizational properties ofgestalt figures and the phenomenon of global preference to create displays that allow immediate understanding of relevant information on the location, identity, and concentration of friendly and enemy units. The data is then compressed temporally, bringing battle dynamics into a useful time domain.

Approved for public release; distribution unlimited.ii REPORT DOCUMENTATION PAGE Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing the burden, to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. REPORT DATE (DD-MM-YYYY) May 20052. REPORT TYPE ARL-TR-3525 SPONSOR/MONITOR'S ACRONYM(S) 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES)U.S. Army Research Laboratory 2800 Powder Mill Road Adelphi, MD 20783-1197 SPONSOR/MONITOR'S REPORT NUMBER(S) DISTRIBUTION/AVAILABILITY STATEMENTApproved for public release; distribution unlimited. SUPPLEMENTARY NOTES ABSTRACTThe Future Force is the linchpin of the Army's modernization plan. It is a concept embracing the integration of new technology, especially information technology, and revolutionary operational concepts to create a force that totally dominates future land operations across the full spectrum of military operations. The Department of Defense Horizontal Fusion portfolio supports the Future Force goal of revolutionizing the digitization and distribution of information to all echelons, including the rifleman at the edge of battle. This report briefly describes a novel system for providing distributed information technology at the warrior's edge, Soldier reactions to the system, and a critical human factors challenge to such a system's use.

System performance is often described in ternis MIPS, MFLOPS, IO bus speed, etc. However; these diniensions are not very useful in characterizing overall systeni performance when part of the systeni is not silicom based (e.g., when there is a human user). Thus in wishitig to address overall system perforniance in niart-machine systems we rnust toss the user irzto the lray. How should this be done? Often, we just ask users how they like fhc particular configuration. We have, after ail, been inculcated with the dictum, "Honor thy user. " and it isn't far from that pronouncement to, "The user knows best." Thus if the user is happy we can expect optimal system peflornzance. O r can we? This paper focuses on the importance of acknowledging general quirky human behavior in the design and evaliiatiott of coniputer displays.

Approved for public release; distribution unlimited. ii REPORT DOCUMENTATION PAGE Form Approved OMB No. 0704-0188Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing the burden, to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number.