Optimal Mechanical Design of Half-Car Vehicle Suspension System Components

In this paper, half-car vehicle suspension was optimized; the free parameters of the optimization are the suspension stiffness and damping coefficients of the components. The main goal of the optimization was to approximately reproduce the behavior of an active suspension model controlled by a state-feedback controller with modifications made to a passive suspension model. Spring component produces a state-feedback signal; this signal is proportional to the displacement. Damper component produces a state-feedback signal that is proportional to the velocity. Therefore, it is possible to map any changes made on the suspension components dynamic characteristics to a state-feedback controller. However, due to the topology of the vehicle suspension, the state-feedback gain matrix must have a definite shape with some elements are set to zero and others may have to satisfy some symmetry conditions. Hence, to alleviate this problem, a constrained optimization problem was proposed. In this constrained optimization problem, a state-feedback controller controlling an active suspension was replaced by modifications to the passive suspension components. As an exemplary problem half-car vehicle suspension was studied rigorously.