1. Active Front Wheel Steering System (AFS) Chapter 2

2. Conventional Steering System Rack and pinion system Constant steering ratio Fully mechanical system

4. AFS Wheel steer angle = superposition of steering wheel angle and AFS actuator Variable steering ratio Combination of mechanical and electrical systems

5. Vehicle Handling Model (without side wind force)

6. Vehicle Handling Model (with side wind force)

7. Assumptions in modeling and control AFS  Fx = 0 (No braking or throttle inputs) -Fyf = Cf  f -Fyr = Cr  r Where Cf = cornering stiffness of front tires Cr = cornering stiffness of rear tires  wheel side slip angle

8. Controller Structure of AFS

9. Wind model

10. Performance Comparison of AFS and non-AFS vehicles

11. Yaw Rate AFS Non-AFS

12. Lateral acceleration

13. Simulation Data m=3950 Iz=6172 Lf=1.1 Lr=1.36 Cf=71600 Cr=77130 Vx=20 Lw=0.4