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A new, systematic approach to the design-evaluation-test product development cycle is described wherein the vehicle design and simulation environments are integrated. This methodology is applied to brake mechanical design and material selection. Time-domain computations within a vehicle dynamic simulation environment account for brake and lining geometry and material properties, actuator properties, and temperature effects. Two examples illustrate the utility of this approach by examining: the effect of varying hydraulic cylinder diameter on passing federally mandated stopping distance tests, and the effect of S-cam actuator adjustment on the performance of air brakes on a tractor-trailer. The simulation results are compared with experimental vehicle stopping distance tests to assess the validity of the simulations.

Recent advancements in three-dimensional digital terrain mapping and vehicle simulation technology present an opportunity to introduce “real-world feedback” early in the design process. Designers of suspension, braking, steering and safety systems can evaluate and optimize designs using computer simulation of a vehicle on the digital proving ground (DPG). A range of possible design behaviors can be identified and analyzed prior to expensive prototyping and testing. Even a series of specific test maneuvers may be evaluated prior to actual testing to ensure safety of the driver and prototype vehicle. As a result, the design process is more efficient and the use of the actual proving ground is more cost effective. This paper presents an overview of the use of the digital proving ground for vehicle design evaluation. Several examples of digital proving ground tests will be discussed.