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Researchers at the US Army Engineer Research and Development Center (ERDC), working in the field of vehicle mobility, have developed methods to predict the physical interactions of vehicles with soil surfaces. This set of methods use research conducted at the ERDC over the last 40 years to predict the physical interactions of vehicles and terrain surfaces under all seasons. Methodologies to measure pertinent terrain properties and assess vehicle performance have also been developed. Much of the work focused on practical applications and is the result of extensive vehicle performance testing and the subsequent analysis of the test results. While there have been attempts to identify and characterize soil media properties using standard soil classification techniques and to assess their effects on vehicle mobility using classical soil mechanics and other theoretical approaches, the current state-of-the-art is such that these approaches have limited practical application.

As a result of increased demand on the range of cargo types that U.S. military tactical trucks must transport, the effect of variations in the mass properties of the cargo on the roll stability of the trucks has become a serious issue. Vehicle dynamics experiments were conducted to obtain roll stability measurements for a tactical cargo truck hauling a broad range of rigid cargo loadings. A simple statics analysis for roll stability and the data obtained during the vehicle dynamics experiments were used to evaluate the relationship between the roll stability of the truck and the mass properties of the cargo. The results of the evaluation demonstrated that roll stability, quantified as the lateral acceleration at the wheel-liftoff threshold, can be accurately characterized as a function of: (1) the lateral center of gravity over the vertical center of gravity and (2) the longitudinal center of gravity over the wheelbase length.

Mission demands for U.S. military tactical trucks require them to transport a broad array of cargo types, including intermodal containers. The wide range of mass properties associated with these diverse cargo requirements has resulted in potential for steering stability issues. The potential for steering stability issues largely originates from the high mobility characteristics of single-unit military tactical trucks relative to typical commercial cargo carriers. To quantify the influence of cargo variations on stability, vehicle dynamics experiments were conducted to obtain steering stability measurements for a tactical cargo truck hauling a broad range of rigid cargo loadings. The basic relationship for the understeer gradient measure of directional response behavior and observed data trends from the physical experiments were used to evaluate the relationship between the steering stability of the truck and the mass properties of the cargo.

The Future Combat System Operational Requirements Document requires that manned and unmanned ground vehicles be capable of negotiating gaps 1.5- to 4.0-meters wide. Gaps include both natural and manmade obstacles. Overcoming battlespace gaps requires the ability to effectively conduct four tasks: prediction, definition, avoidance, and defeat. The inability to overcome gaps within the theater of operations will significantly impair the Future Force's responsiveness, agility, and sustainability. Researchers at the US Army Engineer Research and Development Center (ERDC), working in the field of vehicle mobility have developed methods to predict the physical interactions of vehicles with terrain mechanics. This physics-based simulation method uses research conducted at the ERDC to combine historical empirical laboratory and field evaluations with lumped parameter and numerical analysis to develop a simulated environment of the terrain.