Experimental Testing of a 1994 Ford Taurus for NADSdyna Validation

Starting in 1989, the National Highway Traffic Safety Administration (NHTSA) began researching the use and construction of a new state-of-the-art driving simulator, the National Advanced Driving Simulator (NADS) [1]. A site selection competition among United States universities was conducted, and in 1992, the University of Iowa was selected. As part of the University of Iowa’s cost sharing, they contributed the core vehicle dynamics software for the NADS. This software program, called the Real Time Recursive Dynamics (RTRD) [2], is a minimum coordinate set, multi-body dynamics program that breaks the vehicle chassis and suspension system into a tree topology by cutting closed kinematic loops. This tree topology allows the multi-body system to be solved on parallel computers in real time.

After winning the NADS site selection competition, the University of Iowa supplemented the core vehicle dynamics (RTRD) with a collection of sub-modules that model portions of the vehicle such as the powertrain, tires, brakes, steering system, and aerodynamics that cannot be modeled using multi-body dynamics. The RTRD program containing these sub-modules is called NADSdyna [3].

NHTSA’s Vehicle Research and Test Center (VRTC) in East Liberty, Ohio, is evaluating the NADSdyna vehicle dynamics software, developing vehicle parameter sets for NADSdyna, and enhancing various aspects of NADSdyna. As part of VRTC’s effort, an extensive vehicle testing program to provide “benchmark” data for the simulation evaluation was performed. This paper describes VRTC’s testing of a 1994 Ford Taurus GL passenger car. A similar testing program for an articulated tractor-semitrailer will be described in a later report from VRTC.

NADS is intended to be the most advanced driving simulator in the world when it is operational in the late 1990’s. It is designed to be a research facility that will allow crash avoidance maneuvers and other high severity or dangerous driving situations to be safely studied. The broad scope of the NADS intended uses requires that the vehicle simulation be able to simulate vehicle ride, cornering, driving acceleration, and braking with a high degree of realism. VRTC’s task of evaluating this simulation, therefore, requires a broad testing program covering both mild and severe vehicle ride, cornering, driving acceleration, and braking. The simulation evaluation methodology used is based on past simulation programs at VRTC [4, 5].

pdf source: http://www.nhtsa.gov/DOT/NHTSA/NRD/Multimedia/PDFs/VRTC/ca/capubs/taurus_test.pdf