Engine provides power to the vehicle and that power is transferred to wheel via clutch-gear assembly-differential respectively.The wheels rotate on the road and provide forward motion to vehicle. No road is paved 100% flat,there are irregularities in
form of bumps and cracks. These irregularities exerts vertical force(shocks) on the wheels perpendicular to the road surface and travels a path to the frame(chassis). The force cause unwanted oscillation in vehicle and hampers comfort.When a vehicle encounters a bump,the wheel is displaced vertically upward and loses its contact with the road.
For the proper working of steering system at corners,the wheel needs to be always in contact with the road surface.Therefore there need to a intermediate setup between vehicles body and the wheels so that the above factors wont affect the vehicles performance,stability and comfort.
The suspension system is a geometrical setup that suspends the vehicles body form the wheel assembly .
There are different types of suspension system used in race car vehicles depending upon kind of dynamic parameter intended to be achieve.
I. Double wishbone with direct strut suspension.
II. Double wishbone push rod suspension.
III.Pull rod suspension.
In our recent vehicle we have used double wishbone push rod suspension setup. The geometry of this setup is quiet simple and tuning is easy.
How it works:-
1. Eliminate shock from the ground:-
The setup has spring loaded Dampers .The force from the bump travels a path (line of action of force) via wheel,suspension links and finally gets absorbed due to damping action provided by dampers. The damper gets compressed due to which a highly viscous fluid or air is made to flow through restricted space and which provides the necessary damping action. The damper has spring with certain stiffness value. The spring restores the dampers to initial position or decompresses it so that the vehicle is maintained at the intended height.
2. Maintain stability of vehicle at high speed cornering:-
During high speed cornering different kinds of forces like centrifugal force acts on vehicle.
This force acts in the direction away from centre of turning and tend to topple the vehicle.
The suspension geometry can be tuned to change the tire alignment in such a way so that maximum grip can be achieved between tire and road.