In this paper, an accurate simple model for vehicle handling simulation is obtained. Linearization and model reduction techniques are used to find the simple bicycle model from a complex full vehicle system. First, a large-order model for a full vehicle system is obtained using the linearization from an ADAMS model. Second, the model is divided into two groups: ride motions and handling motions. Among the states, the handling related states are chosen using a model reduction technique (singular perturbation method). Then a simple bicycle model is obtained for the handling simulation and synthesis. The reduced-order handling model results in very accurate reponses compared to the nominal model (based on component data). On the other hand, the nominal model shows discrepancy with the original ADAMS model, specifically in the lateral velocity response. The steady state of the lateral velocity is one of important factors which give effects to the driver (e.g. heading angle). Using the process in the study, it becomes possible to obtain a both accurate and simple model for handling analysis/synthesis. Finally, the model has been used in designing a four wheel steering system in order to demonstrate the benefits of the accurate model. In general, an accurate model reduced the tuning process when the control system is applied back to the original system. In this study, it is shown that the accurate simple model results in a small switching gain of sliding mode four wheel steering system. The gain can not be made arbitrarily large when it is implemented. Therefore, it is clear that obtaining such an accurate handling model becomes cruicial for designing vehicle control systems. The ADAMS full vehicle model in this study does not include compliance effects (e.g. bushing). Therefore, it is recommended that all kinematic joints be replaced with bushing. Then it may be possible to obtain a simple model with increased accuracy. Also, a more complex tire force function should be included (camber thrust, load transfer, ...etc.) in order to compensate the effect of roll and other nonlinear effects.
An accurate simple model for vehicle handling using reduced-order model techniques
Eine einfache Modellierung des Fahrzeug-Handlings
2001
8 Seiten, 5 Bilder, 19 Quellen
Conference paper
English
An Accurate Simple Model for Vehicle Handling using Reduced-order Model Techniques
SAE Technical Papers | 2001
|2001-01-2520 An Accurate Simple Model for Vehicle Handling Using Reduced-order Model Techniques
British Library Conference Proceedings | 2001
|SAE Technical Papers | 2000
|Automotive engineering | 2000
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