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Technology Development for Army Unmanned Ground Vehicles Committee on Army Unmanned Ground Vehicle Technology Board on Army Science and Technology Division on Engineering and Physical Sciences NATIONAL RESEARCH COUNCIL OF THE NATIONAL ACADEMIES THE NATIONAL ACADEMIES PRESS Washington, D.C. www.nap.edu
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THE NATIONAL ACADEMIES PRESS 500 Fifth Street, N.W. Washington, DC 20001 NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance. This study was supported by Contract/Grant No. DAAD 19-01-C-0051 between the National Academy of Sciences and the Department of Defense. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the organizations or agencies that provided support for the project. International Standard Book Number 0-309-08620-5 Additional copies of this report are available from National Academies Press, 500 Fifth Street, N.W., Lockbox 285, Washington, D.C. 20055; (800) 624-6242 or (202) 334-3313 (in the Washington metropolitan area); Internet, http://www.nap.edu Copyright 2002 by the National Academy of Sciences. All rights reserved. Printed in the United States of America
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THE NATIONAL ACADEMIES Advisers to the Nation on Science, Engineering and Medicine The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Bruce M. Alberts is president of the National Academy of Sciences. The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. Wm. A. Wulf is president of the National Academy of Engineering. The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Harvey V. Fineberg is president of the Institute of Medicine. The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy’s purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Bruce M. Alberts and Dr. Wm. A. Wulf are chair and vice chair, respectively, of the National Research Council. www.national-academies.org
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COMMITTEE ON ARMY UNMANNED GROUND VEHICLE TECHNOLOGY MILLARD F. ROSE, Chair, Radiance Technologies, Inc., Huntsville, Alabama RAJ AGGARWAL, Rockwell Collins, Cedar Rapids, Idaho DAVID E. ASPNES, North Carolina State University, Raleigh JOHN T. FEDDEMA, Sandia National Laboratories, Albuquerque, New Mexico J. WILLIAM GOODWINE, JR. University of Notre Dame, Indiana CLINTON W. KELLY III, Science Applications International Corporation, McLean, Virginia LARRY LEHOWICZ, Quantum Research International, Arlington, Virginia ALAN J. McLAUGHLIN, Massachusetts Institute of Technology, Lincoln Laboratory, Lexington ROBIN R. MURPHY, University of South Florida, Tampa MALCOLM R. O’NEILL, Lockheed Martin Corporation, Bethesda, Maryland ERNEST N. PETRICK, General Dynamics Land Systems (retired), Detroit, Michigan AZRIEL ROSENFELD, University of Maryland, College Park ALBERT A. SCIARRETTA, CNS Technologies, Inc., Springfield, Virginia STEVEN E. SHLADOVER, University of California, Berkeley Board on Army Science and Technology Liaisons ROBERT L. CATTOI, Rockwell International (retired), Dallas, Texas CLARENCE W. KITCHENS, IIT Research Institute, Alexandria, Virginia National Research Council Staff ROBERT J. LOVE, Study Director JIM MYSKA, Research Associate TOMEKA GILBERT, Senior Project Assistant ROBERT KATT, Technical Consultant
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BOARD ON ARMY SCIENCE AND TECHNOLOGY JOHN E. MILLER, Chair, Oracle Corporation, Reston, Virginia GEORGE T. SINGLEY III, Vice Chair, Hicks and Associates, Inc., McLean, Virginia ROBERT L. CATTOI, Rockwell International (retired), Dallas, Texas RICHARD A. CONWAY, Union Carbide Corporation (retired), Charleston, West Virginia GILBERT F. DECKER, Walt Disney Imagineering (retired), Glendale, California ROBERT R. EVERETT, MITRE Corporation (retired), New Seabury, Massachusetts PATRICK F. FLYNN, Cummins Engine Company, Inc. (retired), Columbus, Indiana HENRY J. HATCH, Army Chief of Engineers (retired), Oakton, Virginia EDWARD J. HAUG, University of Iowa, Iowa City GERALD J. IAFRATE, North Carolina State University, Raleigh MIRIAM E. JOHN, California Laboratory, Sandia National Laboratories, Livermore DONALD R. KEITH, Cypress International (retired), Alexandria, Virginia CLARENCE W. KITCHENS, IIT Research Institute, Alexandria, Virginia SHIRLEY A. LIEBMAN, CECON Group (retired), Holtwood, Pennsylvania KATHRYN V. LOGAN, Georgia Institute of Technology (professor emerita), Roswell STEPHEN C. LUBARD, S-L Technology, Woodland Hills, California JOHN W. LYONS, U.S. Army Research Laboratory (retired), Ellicott City, Maryland JOHN H. MOXLEY, Korn/Ferry International, Los Angeles, California STEWART D. PERSONICK, Drexel University, Philadelphia, Pennsylvania MILLARD F. ROSE, Radiance Technologies, Huntsville, Alabama JOSEPH J. VERVIER, ENSCO, Inc., Melbourne, Florida National Research Council Staff BRUCE A. BRAUN, Director MICHAEL A. CLARKE, Associate Director WILLIAM E. CAMPBELL, Administrative Officer CHRIS JONES, Financial Associate DEANNA P. SPARGER, Senior Project Assistant DANIEL E.J. TALMAGE, JR., Research Associate
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Preface The Army’s strategic vision calls for transformation to a full-spectrum Objective Force that can project overwhelming military power anywhere in the world on extremely short notice. It must be agile, versatile, and lethal, achieving its objectives through the application of dominant maneuver, precision engagement, focused logistics, information superiority, and highly survivable combat systems. The key to transformation is innovative technology, and the future force will be composed of a family of systems that networks advanced air and ground assets, both manned and unmanned, to achieve superiority in ground combat. Unmanned vehicles, both air and ground, will play a vital role in such a force structure. There are many tasks that unmanned systems could accomplish more readily than humans, and both civilian and military communities are now developing robotic systems to the point that they have sufficient autonomy to replace humans in dangerous tasks, augment human capabilities for synergistic effects, and perform laborious and repetitious duties. Unmanned ground vehicles (UGVs) have the potential to provide a revolutionary leap ahead in military capabilities. If UGVs are developed to their full potential, their use will reduce casualties and vastly increase combat effectiveness. To achieve this potential, however, they must be capable of “responsible” autonomous operation. Human operators may always be needed to make the critical decisions, even to take control of critical events, but it is impractical to expect soldiers to continuously control the movement of unmanned systems. Technologies needed to enable autonomous capabilities are still embryonic. Given technical success, there will be “cultural” programs as soldiers learn to trust robot counterparts. Presentations to the committee and the Demo III demonstrations clearly show that the Army has started down that path and is pursuing many of the enabling technologies. However, without specific requirements to focus the technology base and without funding emphasis, the Army’s efforts are less likely to translate into tactically significant unmanned ground vehicle systems. It is particularly important that there be high-level advocacy to coordinate the generation of requirements and the evaluation and acceptance of system concepts. The Deputy Assistant Secretary of the Army (Research and Technology) requested that the National Research Council’s Board on Army Science and Technology conduct this study to evaluate the readiness of UGV technologies. The study was specifically tasked to examine aspects of the Army UGV program, review the global state of the art, assess technology readiness levels, and identify issues relating to implementing UGV systems as part of the Future Combat Systems program. In addition, the committee was tasked with projecting long-term UGV developments of value to the Objective Force. The committee approached its task by organizing its efforts around the specific technologies and specific charges in the statement of task, subdividing into working groups that could proceed in parallel. Because expertise in many disciplines was necessary to effectively cover all of the elements of robotic vehicles, participants representing many fields were picked from academia and industry (see Appendix A for the biographies of committee members). Several of the committee members had relevant experience in the development, acquisition, testing, and evaluation of combat systems. These members played a vital role, given that concepts for the Future Combat Systems and Objective Force imply many capabilities that have not yet been translated into system requirements. I want to express my personal gratitude to the members who donated their time to this study. They adhered to a demanding schedule, attended numerous meetings and
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demonstrations, and had to review copious quantities of material necessary to effectively carry out the task. The report is theirs and represents the committee’s collective consensus on the current state of technology development for unmanned ground vehicles. Any study of this magnitude requires extensive logistical and administrative support, and the committee is grateful to the excellent NRC staff for making its job easier. Millard F. Rose, Chair Committee on Army Unmanned Ground Vehicle Technology
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Acknowledgments This report has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the National Research Council’s Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the institution in making its published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their review of this report: Harold S. Blackman, Idaho National Engineering and Environmental Laboratory, Johann Borenstein, University of Michigan, Roger W. Brockett, Harvard University, Jagdish Chandra, George Washington University, Paul Funk, LTG, USA, General Dynamics, Jasper Lupo, Applied Research Associates, Larry H. Matthies, Jet Propulsion Laboratory, and Robert E. Skelton, University of California San Diego. Although the reviewers listed above have provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations, nor did they see the final draft of the report before its release. The review of this report was overseen by Thomas Munz. Appointed by the National Research Council, he was responsible for making certain that an independent examination of this report was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content of this report rests entirely with the authoring committee and the institution.
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Contents EXECUTIVE SUMMARY 1 1 INTRODUCTION 13 Background, 13 Report Organization, 16 2 OPERATIONAL AND TECHNICAL REQUIREMENTS 17 Operational Requirements, 17 Technical Requirements for UGV Capabilities, 19 UGV Configurations, 19 3 REVIEW OF CURRENT UGV EFFORTS 30 Army Science and Technology Program, 30 Other Initiatives, 32 4 AUTONOMOUS BEHAVIOR TECHNOLOGIES 42 Perception, 42 Navigation, 51 Planning, 55 Behaviors and Skills, 58 Learning/Adaptation, 65 Summary of Technology Readiness, 68 5 SUPPORTING TECHNOLOGIES 72 Human–Robot Interaction, 72 Mobility, 76 Communications, 79 Power/Energy, 83 Health Maintenance, 87 Summary of Technology Readiness, 91 6 TECHNOLOGY INTEGRATION 94 Status of Unmanned Ground Vehicle System Development, 94 Life-Cycle Support, 96 Software Engineering, 97
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Computational Hardware, 99 Assessment Methodology, 100 Modeling and Simulation, 102 7 ROADMAPS TO THE FUTURE 104 Milestones for System Development, 104 Time Lines for Generic UGV Systems, 109 8 FINDINGS AND RECOMMENDATIONS 111 Technology Development Priorities, 111 Focus on Compelling Army Applications, 112 Systems Engineering Challenge, 113 Advocate for UGV Development, 114 REFERENCES 116 APPENDIXES A Committee Member Biographical Sketches 123 B Meetings and Activities 125 C Autonomous Mobility 127 D Historical Perspective 151
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Figures, Tables, and Boxes FIGURES ES-1 UGV technology areas, 4 ES-2 Time lines for development of example UGV systems, 10 1-1 Army transformation to the Objective Force, 15 4-1 Areas of technology needed for UGVs, 43 4-2 Autonomous behavior subsystems, 44 4-3 Perception zones for cross-country mobility, 46 4-4 User interface for controlling a formation of robot vehicles, 63 4-5 User interface for perimeter surveillance, 63 4-6 User interface for a facility reconnaissance mission, 64 4-7 Probability of success, 65 5-1 Areas of technology needed for UGVs, 73 5-2 Schematic of typical hybrid electric power train for UGVs, 86 5-3 System mass as a function of mission energy requirements, 87 5-4 Hybrid UGV 50-watt to 500-watt systems, 87 6-1 Life-cycle cost decisions, 98 7-1 Evolution of UGV systems, 105 7-2 Possible evolution of UGV system capabilities, 105 7-3 Notional FCS acquisition program, 106 7-4 Time lines for development of sample UGV systems, 107 7-5 Technology development roadmap for the Searcher, 107 7-6 Technology development roadmap for the Donkey, 108 7-7 Technology development roadmap for the Wingman, 108 7-8 Technology development roadmap for the Hunter-Killer, 109 7-9 Technology roadmap for development of generic “entry-level” systems in capability classes, 110 C-1 Pedestrian detection, 133 C-2 Demo III vehicle and PerceptOR vehicle, 136 C-3 Perception of traversable slope as an object, 136 C-4 Color-based terrain classification, 137
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C-5 Tree-line detection, 139 C-6 Geometric challenge of negative obstacles, 141 C-7 Negative obstacle detection using stereo video, 141 D-1 Autonomous land vehicle (ALV), 153 D-2 ALV and Demo II operating areas, 154 D-3 Demo II vehicle and environment, 156 D-4 Stereo obstacle detection results, 157 TABLES ES-1 Example Systems Postulated by the Committee, 3 ES-2 Estimates of When TRL 6 Will Be Reached for Autonomous Behavior and Supporting Technology Areas, 5 ES-3 Capability Gaps in Autonomous Behavior Technologies, 6 ES-4 Capability Gaps in Supporting Technology Areas, 8 2-1 UGV Capability Classes, Example Systems, and Potential Mission Function Applications, 20 2-2 Relative Dependence of Technology Areas for Each UGV Class, 20 2-3 Searcher: Basic Capabilities for an Example of a Small, Teleoperated UGV, 22 2-4 Donkey: Basic Capabilities for an Example of a Medium-Sized, Preceder/Follower UGV, 24 2-5 Wingman: Basic Capabilities for an Example of a Medium-Sized to Large Platform-Centric UGV, 27 2-6 Hunter-Killer Team: Basic Capabilities for a Small and Medium-Sized Marsupial Network-Centric UGV Team, 29 4-1 Criteria for Technology Readiness Levels, 44 4-2 Perception System Tasks, 45 4-3 Technology Readiness Criteria Used for Perception Technologies, 49 4-4 TRL Estimates for Example UGV Applications: On-Road/Structured Roads, 49 4-5 TRL Estimates for Example UGV Applications: On-Road/Unstructured Roads, 50 4-6 TRL Estimates for Example UGV Applications: Off-Road/Cross-Country Mobility, 50 4-7 TRL Estimates for Example UGV Applications: Detection of Tactical Features, 50 4-8 TRL Estimates for Example UGV Applications: Situation Assessment, 50 4-9 Estimates for When TRL 6 Will Be Reached for Autonomous Behavior Technology Areas, 68 4-10 Capability Gaps in Autonomous Behavior Technologies, 69 5-1 Desired Criteria for a High-Mobility UGV Weighing Less Than 2,000 Pounds, 76 5-2 Current Options for Army UGV Mobility Platforms, 77 5-3 Summary of Power/Energy Systems, 85 5-4 Estimates for When TRL 6 Will Be Reached in UGV Supporting Technology Areas, 91 5-5 Capability Gaps in Supporting Technology Areas, 92 C-1 Sample Environments and Challenges, 129 C-2 Imaging Sensor Trade-offs, 143 C-3 Sensor Improvements, 143 C-4 Impact of Feature Use on Classification, 146 D-1 Performance Trends for ALV and Demo II, 158
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BOXES 1-1 A Glimpse of the Future, 14 3-1 Task Statement Question 2.a, 31 3-2 Task Statement Question 2.b, 31 3-3 Task Statement Question 2.c, 39 3-4 Task Statement Question 3.c, 41 4-1 Task Statement Question 4.a (Perception), 51 4-2 Task Statement Question 4.a (Navigation), 54 4-3 Task Statement Question 4.a (Planning), 59 4-4 Task Statement Question 4.b (Tactical Behaviors), 61 4-5 Task Statement Question 4.b (Cooperative Behaviors), 66 4-6 Task Statement Question 4.a (Learning/Adaptation), 68 4-7 Task Statement Question 3.d (Autonomous Behavior Technologies), 71 4-8 Task Statement Question 4.c (Autonomous Behavior Technologies), 71 5-1 Task Statement Question 4.b (Human–Robot Interaction), 75 5-2 Task Statement Question 4.b (Mobility), 79 5-3 Task Statement Question 4.b (Communications), 82 5-4 Task Statement Question 4.b (Power/Energy), 88 5-5 Task Statement Question 4.b (Health Maintenance), 91 5-6 Task Statement Question 3.b, 91 5-7 Task Statement Question 3.d (Supporting Technology Areas), 93 6-1 Task Statement Question 5.c, 99 7-1 Task Statement Question 5.a, 110 8-1 Task Statement Question 3.a, 113 8-2 Task Statement Question 5.b, 115
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Acronyms and Abbreviations AADL Avionics Architecture Definition Language ACC adaptive cruise control ACN assign commercial network ACS agile combat support ALN adaptive logic networks ALV autonomous land vehicle ALVINN autonomous land vehicle in a neural network AMCOM Army Aviation and Missile Command AMUST-D Airborne Manned/Unmanned System Demonstration AOE automated ordnance excavator ARL Army Research Laboratory ARTS-FP All-purpose Remote Transport System-Force Protection ARTS-RC All-purpose Remote Transport System-Range Clearance ARV armed reconnaissance vehicle ASA (ALT) Assistant Secretary of the Army (Acquisition, Logistics, and Technology) ASB Army Science Board ASTMP Army Science and Technology Master Plan ATD Advanced Technology Demonstration ATR automated target recognition ATV all-terrain vehicle AVRE Armored Vehicle Royal Engineers BAST Board on Army Science and Technology BDA battle damage assessment BLOS beyond line of sight BUGS Basic UXO Gathering System C2 command and control CAT crew integration and automation testbed CCD camouflage concealment deception CECOM Communications Electronics Command CET combat engineer tractor CIS communications interface shelter CJCS Chairman, Joint Chiefs of Staff CMU Carnegie Mellon University COP common operation picture COTS commercial off-the-shelf
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CTA Collaborative Technology Alliance CVA canonical variate analysis DARPA Defense Advanced Research Projects Agency DGPS differential global positioning system DOD Department of Defense DOE Department of Energy DRP dynamic remote planning DSP digital signal producer DSRC dedicated short-range communications DTED digital terrain elevation data DUECE deployable universal combat earthmover EEA essential elements of analysis EOD explosive ordnance disposal EWLAN enhanced wireless local area network FCC Federal Communications Commission FCS Future Combat Systems FDIR fault detection, identification, and recovery FFN friend, foe, or neutral FLIR forward looking infrared radar FOC Future Operational Capabilities FOLPEN foliage penetration FPGA field programmable gate arrays FY fiscal year GIPS giga instructions per second GIS geographical information systems GLOMO global mobile GOPS giga operations per second GPS Global Positioning System HAZMAT hazardous materials HCI human–computer interface HMI human–machine interface HMMWV high-mobility multi-purpose wheeled vehicle HRI human–robot interaction IFF identification of friend or foe IFFN identifying friends, foes, and noncombatants IFOV instantaneous field of view IMU inertial measurement unit INS inertial navigation system IR infrared JAUGS Joint Architecture for Unmanned Ground Systems JFCOM Joint Forces Command JPL Jet Propulsion Laboratory JRP Joint Robotics program JTRS Joint Tactical Radio System JVB Joint Virtual Battlespace LADAR laser detection and ranging LAN local area network
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LORAN long-range navigation LOS line of sight LPD low probability of detection LPI low probability of intercept LSI lead system integrator M&S modeling and simulation MARDI Mobile Advanced Robotics Defense Initiative MARS Mobile Autonomous Robot Software MC2C multisensor command and control constellation MDARS-E Mobile Detection Assessment Response System-Exterior MDARS-I Mobile Detection Assessment Response System-Interior MEP Mobility Enhancement program MFLIR+R monocular forward looking infrared plus radar MILS multiple independent levels of security MIPS million instructions per second MNS mission needs statement MOE measure of effectiveness MOP measures of performance MOPS million operations per second MOUT military operations in urban terrain MOV measure of value MPRS Man-Portable Robotic System MURI Multidisciplinary University Research Initiative MV+R monocular video plus radar NASA National Aeronautics and Space Administration NBC nuclear, biological, chemical NC-AGV network-centric autonomous ground vehicle NIST National Institute of Standards and Technology NLOS non–line of sight NLP natural language processing NRL Naval Research Laboratory OAR organic air vehicle ODIS Omni-Directional Inspection System OMG Object Management Group OO object-oriented OP observation post ORD operational requirements document OSD Office of the Secretary of Defense PC-AGV platform-centric autonomous ground vehicle PerceptOR Perception off-road PM program manager PRIMUS Program of Intelligent Mobile Unmanned Systems QoS quality of service RACS robotics for agile combat support RAIM receiver autonomous integrity monitoring RALPH rapidly adapting lateral position handler RBF radial basis function RCRV remote crash rescue vehicle RCSS Robotics Combat Support System
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RDA Research, Development, and Acquisition RF radio frequency RGB red, green, blue RONS Remote Ordnance Neutralization System RSTA reconnaissance, surveillance, and target acquisition S&T science and technology SA situational awareness SAE Society of Automotive Engineers SAF-UGV semiautonomous follower unmanned ground vehicle SAP/F-UGV semiautonomous preceder-follower SARGE Surveillance and Reconnaissance Ground Equipment SDD system development and demonstration SEAD suppression of enemy air defenses SFLIR stereo forward looking infrared SLOC source lines of code SOP standard operating procedure SORC statement of required capabilities SPC software process control SRS Standardized Robotics System STO science and technology objective STRICOM Simulation, Training, and Instrumental Command SV stereo video SWAT special weapons and tactics SYRANO Systeme Robotise d’Acquisition pour la Neutralisation d’Objectifs TACOM Tank-Automotive and Armaments Command TARDEC Tank-Automotive Research, Development, and Engineering Center TGV teleoperated ground vehicle TMR tactical mobile robot TRAC TRADOC Analysis Center TRADOC Training and Doctrine Command TRL technology readiness level UAV unmanned air vehicle UCAV unmanned combat air vehicle UDS UCAV Demonstration System UGCV unmanned ground combat vehicle UGV unmanned ground vehicle UOS UCAV Operating System URPR University Research Program in Robotics USD-AT&L Under Secretary of Defense for Acquisition, Technology and Logistics USDOT U.S. Department of Transportation UUV unmanned underwater vehicle UWB ultra-wide band UXO unexploded ordnance VCI vehicle cone index VTOL vertical takeoff and landing XUV experimental unmanned vehicle