Double Wishbone kinematic modeling

Description

The suspension is an important mechanical system in road vehicles. A typical suspension system consist in links, control arms, bushing, spring, damper and bump-stop. The rigid parts, i.e. links and control arms determine the kinematic of the suspension and the force elements, i.e. spring, damper and bump-stop define the forces that the suspension, with a generalize motion (road irregularities), will apply to the chassis. We can see on Fig. 1, some common suspension systems in passenger cars.

The function of a suspension system can be categories into:

Safety

• Ensure the maximum contact between the tires and the road,
• Mantain the wheel in a proper alignment,
• Carry the car and passengers weight.

Comfort

• Limit the travel distance of the chassis,
• Reduce the vertical accelerations,
• Absorb the impacts of the road (irrugularities, obstacles and holes).

References

[1] Rill, G.: Road Vehicle Dynamics - Fundamentals and Modeling, Taylor & Francis, Boca Raton, 2011.