Automated Methods for Converting a Non Real-time Cartesian Multi-body Vehicle Dynamics Model to a Real-time Recursive Model

摘要

The United States Army Research, Development, and Engineering Command's Tank Automotive Research, Development and Engineering Center (U.S. Army RDECOM-TARDEC) laboratories is seeking to advance modeling and simulation methods used for predicting the performance of ground vehicles. TARDEC typically generates non-real-time models of its vehicles using DADS: a general purpose commercial, multi-body software package based on a Cartesian coordinate formulation. TARDEC also currently uses SimCreator to develop real- time multi-body vehicle models. SimCreator uses recursive techniques to perform the simulations in real-time. The goal of the study presented here was to develop rapid conversion methods for translating models of DADS and other commercial multibody software packages into SimCreator models. A procedure that can be automated was developed to convert a DADS model of a High-Mobility Multipurpose Wheeled Vehicle (HMMVW) to a SimCreator model. The vehicle model consisted of the chassis base body and the 4 wheels connected to it with double A-Arm suspensions and steering constraints. This model with 2 closed kinematic loops at each suspension was preprocessed to determine the best joints to be used as constraints (cut joints). The Cartesian joint coordinates of the DADS models were converted to relative joint coordinates used by SimCreator. Bodies, joints, and force elements were then converted using the components from SimCreator's multi-body dynamics library. In place of the radial spring tire model used in the DADS simulation, a multi-disc tire model was developed to be used with SimCreator.