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Geospatially enriched synthetic environments are needed for development and assessment of unmanned ground vehicle (UGV) performance to support sensor fusion and sense making. This work will address how the high-fidelity/resolution environment is achieved and integrated to inform simulations addressing critical questions. We will investigate a multi-resolution modeling capability to inform development of a high-fidelity synthetic environment (HFSE) testbed and to link to other models and simulations. This report will discuss results and lessons learned in developing an engineering- and operational-level experiment for proof of concept.

Future Combat Systems will include Small Unmanned Ground Vehicles (SUGV). Several have already been deployed, including the TALON(R), an 80-lb SUGV; PackBot(R) at 50 lb, and Gator(TM) at 2500 lb. As doctrine, tactics, techniques, and procedures continue to evolve, there exists a need to represent the performance of these vehicles in Army models and simulations. Army simulations such as COMBATXXI and OneSAF will use the Standard Mobility Application Programmers Interface (STNDMob API) for estimating vehicle performance. Currently, only the Gator can be represented by a STNDMob vehicle class, and it is modeled as a manned vehicle. This report describes the results of a study undertaken to identify and discuss mobility performance algorithms applicable to SUGV in the weight range of 10 to 5000 lb. Algorithms used by the NATO Reference Mobility Model and the STNDMob were examined. Most of the algorithms currently used in STNDMob were found to be applicable to SUGV. However, it was found that vehicle performance data and algorithms for additional material surfaces and obstacles need to be developed; specifically, models and data for wheeled vehicle skid steering, interior building floor and roof surfaces, and stair climbing are needed. Previously unreported SUGV test results for TALON, MATILDA, and PackBot are presented, and performance estimates described herein compared well using currently available algorithms in STNDMob. Recommendations for new algorithms and improvements to current mobility algorithms are presented., The original document contains color images. Prepared in collaboration with Cold Regions Research and Engineering Lab., Hanover, NH and Army Materiel Systems Analysis Agency, Aberdeen Proving Ground, MD.

Achieving semantic interoperability between simulation systems and Command and Control (C2) systems continues to be a challenging area of research and development. One area of considerable study is development of a common representation of the maneuver network to obtain consistency in the results computed by simulations and C2 systems when determining how a ground force will move through some portion of the battle space. The Common Maneuver Network (CMN) program has implemented and demonstrated the ability to obtain consistent results from the One Semi-Automated Force (OneSAF) and an Army C2 system (Army Battle Command System). Moreover, the Army's Assured Mobility concept calls for establishing the mobility common operational picture (M-COP) facilitating command decision-making regarding how best to deploy, move, and maneuver, by ground or vertical means, where and when desired, without interruption or delay, to achieve the intent. The Department of Defense Global Information Grid (GIG) will play a central role in composing the M-COP as a focus area of interest to land warfare decision makers. Network centric operations require the integration of complex communications networks, data from disparate sources, and service-oriented software applications. In the GIG, data and information necessary for the M-COP will be made available through discoverable and callable web-based services to the spectrum of users, software agents, and software systems. The use of ontologies to formally represent data semantics and knowledge combined with service based software architectures provides new opportunities for the integration of command and control systems, simulations, models, and dynamically changing data. This paper describes concepts and architecture for an experiment to further investigate and demonstrate the use of knowledge-based technologies to support tactical maneuver. Automated route planning, route monitoring and intelligent software-initiated route changes are provi

Information needed to support ground mobility decision making is critical to the success of ground operations. The ability to rapidly obtain and process relevant information in a network-centric environment will empower warfare planners. In addition, future network centric operations that will include autonomous unmanned ground vehicles as envisioned in the Future Combat Systems program will increasingly require the exchange of well-structured information between human forces and robotic systems. Addressing this operational challenge begins with a clear understanding of the information content needed for ground mobility planning. The purpose of the Mobility Common Operational Picture (M-COP) project is to specify a standardized vocabulary and conceptual relationships for the expression and transfer of ground vehicle maneuver data, planned routes, trafficability assessments, and other parameters associated with Future Force assured mobility across Modeling and Simulation (M&S) systems and Battle Command (BC) systems. The scope of the project was limited to ground vehicle mobility and ground vehicle maneuver information. The project identified terms and concepts across relevant data representations that will enable the M-COP capability to be achieved in the current and emerging network centric architecture., The original document contains color images.

In Prospective Issues in Simulation Model Composability: Basic Concepts to Advance Theory, Methodology and Technology, a three-tier strategy is suggested to advance the composability infrastructure. Advances in the infrastructure are predicated on the developments in theory, methodology, and technology. Better understanding of the conceptual models of composable simulations is argued to be critical in improving the technology for composition. In particular, making context a significant component of such a conceptual model, and capturing, packaging, and distribution of the context is suggested to improve qualification of simulation models for composition. The notion of an agent-mediated model base technology that uses intelligent matchmaking and brokering mechanisms to operate on such context specification objects is suggested. The article 'Terrain Surface Codes for an All-Season, Off-Ride Motion Simulator describes the approach taken to relate terrain mechanics properties with the terrain database, in sufficient detail to support the TARDEC Ride Motion Simulator and additionally, allow consistency when interacting with Semi-Automated Force (SAF) vehicles within the OneSAF Test Bed (OTB), OneSAF Objective System (OOS) and potentially other simulators or simulations., Contains two articles - Prospective Issues in Simulation Model Composability: Basic Concepts to Advance Theory, Methodology and Technology by Levent Yilmaz and Tuncer I. Oren, p1-8, and Terrain Surface Codes by Paul W. Richmond, Alexander A. Reid, Sally A. /Shoop, and George L. Mason.

To meet information needs of operational commanders, user-centric applications will combine Global Information Grid (GIG) data and services to create a Common Operational Picture (COP). The COP, a single identical display of relevant information shared by more than one command, will facilitate collaborative planning and situational awareness. Land warfare decision-makers are particularly interested in ground vehicle mobility characteristics of the battlespace. This paper describes both the Mobility-COP, from which warfighters can assess the ability of forces to maneuver effectively under multiple environmental and tactical conditions, and a formal ontology design to achieve the Mobility-COP in the future GIG net-centric architecture., Published in CrossTalk: The Journal of Defense Software Engineering, v19 n7 p26-30, July 2006.

Crosstalk's mission is to encourage the engineering development of software to improve the reliability, sustainability, and responsiveness of our warfighting capability. Articles in this journal issue include: DoD CIO: the Net-centric Information Enterprise; Information Sharing is a Strategic Imperative; Designing and Implementing an Assured National Security Enterprise; Serve-Oriented Architecture in Net-Centric Operations, Creating the Enabling Capability to Conduct Net-Centric Operations, Overview of the Dept. of Defense Net-Centric Data Strategy, Transformational Communications: Systems for DoD Net-Centric Operations; Development of a Ground Vehicle Maneuver Oncology to Support the Common Operational Picture.

Mobility implementation in military models and simulations (M&S) currently is tailored primarily for specific models, leading to inconsistency between models. To assist decision-makers in analysis, acquisition, and training activities, it is necessary to provide and promote consistency among the models. The NATO Reference Mobility Model (NRMM), Version II, is the Army Battle Command, Simulation and Experimentation Directorate, standard for single vehicle ground movement representation. This report describes the development of an NRMM-based Standard Mobility (STNDMob) Application Programming Interface (API) as a means of readily achieving higher fidelity movement representation by incorporating terrain-limited speeds into M&S. As described in the report, the STNDMob API, Version 3, includes descriptions of two derivative models: the low-resolution (Level 1) and the medium-resolution (Level 2) capabilities of STNDMob within the tactical/entity fidelity. Each level of resolution has two degrees of fidelity. These levels of resolution are an implementation of the physical models for steady-state speed conditions. As a whole, STNDMob can be classified as a service module that provides vehicle speeds to a vehicle routing service/planner., Prepared in collaboration with North Wind, Inc., Vicksburg, MS.

Central heating plants are often used on large building complexes such as university campuses or military bases. Utilidors can be used to contain heat distribution lines and other utilities between a utility station and serviced buildings. Traditional thermal analysis of utilidors is one-dimensional, with heat transfer correlations used to estimate the effects of convection, radiation, and two-dimensional geometric effects. The expanding capabilities of computers and numerical methods suggest that more detailed analysis and possibly more energy-efficient designs could be obtained. This work examines current methods of estimating the convection and radiation that occur across an air space in square and rectangular enclosures and compares them with numerical and experimental data.

US Army Corps of Engineers® Cold Regions Research & Engineering Labórate UBRAEI AUG2T W0 -DrT^TöT^ecrämäüon ..K w ag igcsa. Two-Dimensional AnalyslroTNatural Convection and Radiation in Utilidors Paul W. Richmond June 1999 n an Abstract: Central heating plants are often used on large building complexes such as university campuses or military bases. Utilidors can be used to contain heat distribution lines and other utilities between a utility sta­tion and serviced buildings. Traditional thermal analy­sis of utilidors is one-dimensional, with heat transfer correlations used to estimate the effects of convection, radiation, and two-dimensional geometric effects. The expanding capabilities of computers and numerical methods suggest that more detailed analysis and pos­sibly more energy-efficient designs could be obtained. This work examines current methods of estimating the convection and radiation that occur across an air space in square and rectangular enclosures and compares them with numerical and experimental data. Cover: Construction of a utilidor at Eielson AFB, Alaska. (Photo courtesy of Dr. Gary Phetteplace.) How to get copies of CRREL technical publications: Department of Defense personnel and contractors may order reports through the Defense Technical Information Center: DTIC-BR SUITE 0944 8725 JOHN J KINGMAN RD FT BELVOIRVA 22060-6218 Telephone 1 800 225 3842 E-mail help@dtlc.mil msorders@dtic.mll WWW http://www.dtic.mil/ All others may order reports through the National Technical Information Service: NTIS 5285 PORT ROYAL RD SPRINGFIELD VA 22161 Telephone 1 800 553 6847 or 1 703 605 6000 1 703 487 4639 (TDD for the hearing-impaired) E-mail orders@ntis.fedworld.gov WWW http://www.ntis.gov A complete list of all CRREL technical publications is available from USACRREL (CEERD-IM-HL) 72 LYME RD HANOVER NH 03755-1290 Telephone 1 603 646 4338 E-mail techpubs@crrel.usace.army.mil For information on all aspects of the Cold Regions Research and Engineering Laboratory

Before vehicle mobility in snow can be reliably predicted, a complete understanding of motion resistance in snow is required. This report examines several aspects of wheeled vehicle motion resistance using results obtained with the CRREL instrumented vehicle. Resistances of leading and trailing tires are examined. Limited data are presented for undercarriage drag, and third and fourth wheel passes in the same rut are initially analyzed, as is how snow deforms around a wheel. For the CRREL instrumented vehicle, a trailing tire has a resistance coefficient of about 0.017 for snow depths less than about 22cm. For deeper snow, the disruption of the snowpack caused by a preceding wheel causes snow to fall into the rut, resulting in higher trailing tire coefficients. For larger vehicles, which in some cases have trailing tires carrying larger loads than preceding tires, the trailing tire coefficients are on the order of 0.048 and 0.025 for second and third trailing wheels respectively. Since there are no trailing tire data available for these larger vehicles, these values are based on nonlinear regression analysis, which includes a prediction of the leading tire resistance. The results and observations of this study are applied in a reanalysis of the towed resistance data obtained during the U.S. Army's Wheels vs. Tracks study. An improved algorithm is presented for predicting wheeled vehicle motion resistance caused by snow. (AN)

This report annotates the cold regions mobility prediction routines included in the CAMMS/ALBE mobility models. It further explains the development of the algorithms that are used in these models to describe the interaction of a vehicle with terrain that has been affected by cold weather. The following terrain conditions are discussed: undisturbed snow (shallow and deep); disturbed snow (moderately trafficked and hard packed); ice; and thawing soils. Several combinations of substrates are also considered. A stand-alone computer model is included. (MM)

Light Infantry Division elements require a system to allow them to conduct semi-autonomous operations and limited self-resupply with existing wheeled vehicles in snow deeper than 15 cm. Since many roads and trails will not have been kept open prior to deployment, truck-mounted plows (if available) would be ineffective. In most instances, heavy tracked vehicles, which can cause extensive environmental damage, are required to move deep snow. Over-snow vehicles can be equipped with front- or rear-mounted plow blades. But to adapt a plow to the U.S. Army's only over-snow vehicle, the small unit support vehicle (SUSV), would require major vehicular modifications. A towed plow assembly for the SUSV was proposed. To adapt the plow for this application, a unique four-bar parallel linkage towing assembly was developed, which bolts directly on to the SUSV's pintle hook mounting bracket. This assembly controls the pitch, and the plow geometry stabilizes the roll of an attached plow. The plow was constructed primarily of aluminum, has three plowing widths, and can be towed over the road (minimum width 2.3 m). This report describes the design, operation and results of field tests of the towing assembly and plow. The SUSV successfully towed the plow through deep (85 cm) unbonded snow, creating a path wide enough for a wheeled vehicle. In hard, dense, wind-blown snow the plow was less successful, requiring several passes to open a trail. No major failures occurred, although some minor problems were identified, and recommendations for design improvements are presented.

Winter logistical operations employing wheeled vehicles are severely restricted because of traction losses in deep snow. To enable the use of wheeled vehicles for off-road winter deployment, an independent drag-plow was developed to be attached to the pintel mount of the U.S. Army's small unit support vehicle (SUSV). Small-scale testing revealed significant stability problems with a towed wedge-shaped plow model. Geometric modifications to the plow design and a 4-bar parallel motion towing linkage were developed to stabilize plow roll and pitch, respectively. A welded aluminum half-width model incorporating these modifications was successfully tested at Keweenaw Research Center in northern Michigan in January 1991. Parameters measured during testing included pitch and roll angles, drawbar forces, speed, plowed path geometry, and snow characteristics. These parameters were used to determine the feasibility of a full-scale model capable of plowing a 2.45-m path in 1-m-deep low density snow, leaving 15 cm of snow as ground cover. The model performed well in medium density snow, with drawbar forces in the 5.6-kN range. Plow penetration was limited by a geometric constraint of the 4-bar linkage, with 15 deg the approximate maximum link angle from horizontal. Pitch and roll stability in off- road applications was excellent, with the plow demonstrating an ability to right itself and dig in after encountering obstacles. Successful half-width tests have proven the concept of utilizing a SUSV-towed V-plow for clearing access roads in deep snow for off-road winter operations. Data extrapolation of half-width tests demonstrates that a full-scale plow is feasible.

Observations and experiments have shown that the transfer is greater for water flowing over ice than for water flowing over flat plates without melting. The mechanisms that contribute to this increased heat transfer are not completely understood. One possible cause is the density inversion of water at 4 C. In order to investigate this effect on heat transfer, a small open-channel flume was designed and constructed. Experiments were conducted with the flume bed at temperatures slightly above 0 C and at temperatures above 4 C. Bulk water temperatures ranged from 5 to 33 C. Flow data were obtained for 2500 < Re sub H < 100000. At high flow rates (fully developed turbulent flow) heat transfer correlations obtained from these experiments initially showed higher heat transfer rates than those obtained from experiments in larger flumes with ice present. This thought to be due to a difference in velocity profiles caused by the flume width. Once velocity corrections were made to the data, they agreed more closely with experiments from wider flumes. The results indicate that the density inversion of water could account for most of the increased turbulent heat transfer observed between melting and nonmelting systems. The heat transfer data at low flow rates are more qualitative than quantitative due to difficulty in obtaining accurate data. Keywords: Freshwater ice, Heat transfer, Ice covers, Water flows.

The primary goal of this study was to validate the shallow snow mobility model. As previously mentioned, this model is based on theoretical relationships and empirical expressions developed in the past, and a large, but scattered, data base. Since the shallow snow model has not appeared in the literature in the past, we begin by describing the approach used in version 1.0 (SSM1.0) for predicting mobility. The two principal quantities that govern mobility are traction and motion resistance. Commonly, two types of traction (net and gross) and two types of motion resistance (internal and external) are identified.

This report presents and analyzes winter mobility data obtained during the winters of 1988 and 1989 at the Keweenaw Research Center, Houghton, Michigan. Traction data (1989) for the HMMWV, HEMTT, SUSV and M60 military vehicles, and the CRREL instrumented vehicle, are presented for hard-packed snow and for undisturbed snow overlaying ice. When these data are compared with an equation for undisturbed snow over soil or packed snow, slight reductions in traction are observed. Resistance data obtained in 1988 and in 1989 are evaluated based on a combined vehicle-snow parameter. An empirical equation based on this parameter and data from all the vehicles, including the CRREL instrumented vehicle using several different width tires, is developed. The resistance data and the empirical resistance equation are compared with the CRREL shallow snow mobility model (SSM2.0). The SSM2.0 predicted resistance is within 50% on average. The empirically derived resistance equation is slightly worse. The report recommends further research on vehicle motion resistance in snow.

For snow with an initial density of less than 0.45 Mg/cu m, load transfer through shallow snow is shown to be attenuated by an interfacial boundary force. Evidence is presented that shows the existence of a density distribution in the deformed area. Results of a laboratory plate-sinkage test on sintered snow support this analysis. Maximum value obtained for the interfacial boundary force range from 1335 to 2670 N when the average density of the deformed area is about 0.5 Mg/cu m.

This report describes an attempt to develop a procedure for dynamic calibration of free-filled soil stresses gages embedded in a soil sample. The method presented utilizes a drop-type impact testing machine and a small, instrumented container of soil. The velocity history of a shock pulse applied to the soil sample is measured and the applied stress computed; this value is then compared with data obtained from stress gages embedded in the soil. The results showed that the procedure is adequate for unfrozen soil, but for frozen soil the accuracy in the measurement of compressional wave velocity needs to be increased to obtain useful results. (Author)

This report presents the results of a laboratory test program designed to determine the applicability of two analytical solutions to projectile penetrations in frozen soils. The test program consisted of firing small caliber cylindrical projectiles into frozen soil targets. Four types of 7. 9-mm-diam projectiles were tested: two with a hemispherical nose the other two flat-nosed, with both long (length/diameter = 4) and short (L/D = 2) versions of each nose shape. Penetration depth versus impact velocity data are presented. Comparisons of the data indicate that a flat-nosed projectile is a less efficient penetrator than one of equal weight with a hemispherical nose. A small increase in resistance to penetration is observed for an increased L/D ratio. Two penetration solutions are compared with the test results. One is empirical, based on target strength and projectile characteristics. The other, a closed form solution, is based on the expansion of a spherical cavity in the target material. Modifications and further definition of nose shape coefficients and a mass scaling factor increase the applicability and accuracy of the empirical method to the solution of small arms penetration problems. The closed form solution performed well for impact velocities below 600 m/s. (Author)

Instrumented M374 projectiles were launched into snow, nylon, and Styrofoam targets using a 10.7-m radius centrifuge. For snow of 410-kg/cu m 3 density, the 3.1-kg test projectile experienced decelerations of approximately 220, 400, and 550 m/sq s (at a depth of 0.1 m) for initial impact velocities of 15,30 and 46 m/s respectively. These values disagree with values predicted from a simple hydrodynamic drag force approximation. The decelerations measured for snow targets were always greater than those measured for nylon shaving targets (of density 120 kg/cu m) indicating that this material is not a good analog for snow of the density used in these tests. (Author)