Controllability and Stability Aspects of Actively Controlled 4WS Vehicles 891977
Four wheel steering (4WS) of passenger cars has become a topic of interest in recent vehicle dynamics literature. In the present work, a linear two-degree of freedom model (L2DF) has been used to examine controllability and stability aspects of various 4WS algorithms. Yaw rate r and lateral velocity v were used as model degrees of freedom, and as state feedback variables for the implementation of 4WS controllers of various types. With controllers developed using the L2DF model, investigations were performed into the performance of such controllers when implemented using a nonlinear three-degree of freedom model (N3DF) which included roll and the possibility of tire saturation. Desirable steady-state properties for v and r can be obtained using the robust controllers developed through the use of the L2DF model. Finally, the stability of the system is shown to depend upon tire cornering stiffness, and is examined both qualitatively and quantitatively.
Citation: Ohnuma, A. and Metz, L., "Controllability and Stability Aspects of Actively Controlled 4WS Vehicles," SAE Technical Paper 891977, 1989, https://doi.org/10.4271/891977. Download Citation
Author(s):
Akira Ohnuma, L. Daniel Metz
Pages: 16
Event:
Passenger Car Meeting & Exposition
ISSN:
0148-7191
e-ISSN:
2688-3627
Also in:
SAE Transactions Journal of Passenger Cars-V98-6
Related Topics:
Four wheel steering
Vehicle dynamics /flight dynamics
Mathematical models
SAE MOBILUS
Subscribers can view annotate, and download all of SAE's content.
Learn More »