Study on Influences of Rear-Wheel Turn Angle to Performance of Four Wheel Steering (4WS) Vehicle

The main objective of this project is to study on influences of rear-wheel turn angle to
the performances of 4-wheel-steering (4WS) vehicle. As to determine either the
evaluated performances of 4WS is either an advantage or disadvantage, thus, a datum is
required. Therefore 2-wheel-steering (2WS) system is also included in the study since
the 2WS system does not utilize the rear-wheel turn angle (zero rear-wheel turn angles).
The core problem statement implies in this project is what are the advantages and
disadvantages of 4WS vehicle; is the influences of rear-wheel turn angle to 4WS does
affecting in good or bad way?
Thus, the first scope done in this project is the configuration of the 4WS system shall be
established to correlate how the rear-wheel shall turn accordingly with respect to the
steering-wheel and the front-wheel turn angle. For this study, Honda’s 4WS system is
used. K.N Spentzas and I. Alkhazali stated that to study 4WS vehicle, simplification
shall be made and one of it is the used of two-degree-of-freedom bicycle model. This
model is very useful for analyzing the kinematics of the vehicle (i.e. turning radius,
vehicle side-slip). However, when it comes to dynamic parameters (i.e. wheels side-slip
angle, lateral velocity, yaw velocity), three-degree-of-freedom is desired since certain
elements is essential to get a qualified data.
By referring to recent literatures made related to this project, the quality of the data,
methodology and the procedures to produce them are also been checked beforehand to
ensure that the project is done professionally.
The study includes few critical parameters such as turning radius, yaw velocity, lateral
velocity, and side-slip angles that are necessary to evaluate how the rear-wheel turn
angle affects the vehicle’s performances by comparing those findings between 4WS and
2WS vehicles.