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This paper describes the development of a dual-location driving simulator by researchers at the Virtual Reality Applications Center (VRAC) at Iowa State University. The simulator connects drivers in two highly immersive virtual reality interfaces, the C4 and the C6, both located at VRAC. The vehicle dynamics is computed separately for each vehicle by independent Windows NT systems running VDANL. These systems also perform real-time data acquisition from the vehicle bucks and terrain queries at each dynamics time-step. The vehicles exchange dynamics information including vehicle position and orientation, and their derivatives. VRAC researchers will use the driving simulator for experiments involving collaborative or competitive maneuvering. Applications include the maneuvering of farm vehicles, battlefield simulation and racing.

The continuing increase of routinely available computing power now allows optimization with objective functions based on time domain simulations of vehicle dynamics. This paper uses this technique to determine the steering controls which lead to very large transient lateral load transfer. The vehicle simulation uses a yaw plane vehicle model with a very capable tire model. The steering controls to be optimized are a function of their Fourier coefficients. Examples using a SUV model illustrate that very inexpensive computing platforms are able to implement millions of time domain runs in a reasonably short time in support of the optimization. Comparisons with simulations of the NHSTA fishhook maneuver provide context for the results, which lead to simulated load transfer slightly in excess of the simulated NHTSA test. The optimized runs exhibit maximum load transfer well within the confines of a two lane highway.

The U.S. Army uses the root mean square and power spectral density of elevation to characterize road/terrain (off-road) roughness for durability. This paper describes research aimed toward improving these metrics. The focus is on taking previously developed metrics and applying them to mathematically generated terrains to determine how each metric discerns the relative roughness of the terrains from a vehicle durability perspective. Multiple terrains for each roughness level were evaluated to determine the variability for each terrain rating metric. One method currently under consideration is running a relatively simple, yet vehicle class specific, model over a given terrain and using predicted vehicle response(s) to classify or characterize the terrain.

This study concerns the modeling of the stabilizer bar in a car suspension. This is a crucial and difficult task if its non-linear behavior should be captured correctly. In this study, the modeling of a stabilizer bar is done using beam finite elements based on the absolute nodal coordinate formulation (ANCF). An ANCF beam element is reviewed and its implementation in a multibody dynamics framework is explained. The specific element is chosen since it is assumed to be appropriate for modeling stabilizer bars. To test the feasibility of using the chosen ANCF beam element for modeling stabilizer bars, several numerical studies have been performed. These include eigenfrequency and static analyzes where results obtained using ANCF beam elements are compared with results obtained using other methods.