Abstract
KEYWORDS – On-center handling, steering system, handling control, multi-body dynamics, vehicle dynamics
ABSTRACT –
On-center handling (OCH) refers to some important steering behaviors such as straighttraveling stability, etc. OCH is usually carried out by physical vehicles, and thus is costly, time-consuming and difficult to apply to early stage of design. The objective of this study is to develop a virtual evaluation method for OCH, using multi-body dynamics approch to realize front-loading evaluation of on-center handling performance. The correlation between driver’s rating and physical values of objective judgement has been analyzed by benchmarks and four physical values are identified to represent the driver’s feels. To calculate these physical values, a full vehicle model has been developed by integrating all of the necessary components including non-linear steering stiffness, steering & suspension friction, power-steering unit model, detailed leaf spring and tire model. The model development is driven by measurement data for defining properties and math functions. All of analysis is carried out by Adams/Isuzu, a customized system based on Adams/View. A light-duty truck is used as a modelling target. In this paper, steering effort/lateral acceleration /steering angle data, from both of the tests and the simulation are presented. These results describe very good accuracy and correlation of the method. Also a parametric study is conducted to find some hints for enhancing the quality of on-center handling behavior and show high potential for predicting OCH.