Review Paper on Design, Analysis and Fabrication of “Four-Wheel Steering Mechanism”

Abstract: Four-Wheel Steering (4WS) systems improve vehicle maneuverability, stability, and cornering performance compared to conventional two-wheel steering systems. This paper presents the design, kinematic analysis and fabrication methodology of a purely mechanical four-wheel steering mechanism using linkage-based actuation. The objective is to develop a compact, low-cost and mechanically synchronised 4WS system suitable for small vehicles and prototype applications. The proposed mechanism integrates front and rear steering linkages connected through a central transmission link to ensure proportional steering angles. Kinematic relationships were derived based on Ackermann steering geometry to minimise tyre slip during turning. Structural analysis was performed to assess bending stress in the steering links and torsional stress in the pivot shafts. Mild steel was selected as the primary material based on strength and manufacturability. Fabrication was carried out using conventional machining and welding processes. The developed mechanism demonstrates synchronised steering action at both axles, reduced turning radius and improved directional control. The study confirms that a mechanical linkage-based four-wheel steering system is feasible, cost-effective and suitable for low-speed automotive applications. Key Words: Four-wheel steering, Ackermann geometry, Steering Linkage, Vehicle Dynamics, Turning Radius, Mechanical Fabrication.