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. The terrain mechanics modeling is combined with a 2-dimensional vehicle dynamics model that predicts the traction required to maneuver through deformable terrains or gaps. The vehicle dynamics model is also designed to detect contact between the vehicle chassis and the terrain for vehicle and gap geometry analysis. The contact element is designed to provide both normal resistances during contact and act as a drag component representing the drag resistance between the vehicle chassis and the terrain. The combined terrain mechanics and vehicle dynamics models are called the Vehicle Gap Analysis Program (VGAP).
This paper presents the application of the terrain mechanics research conducted in development of the VGAP and a verification of the VGAP.