Including the Force Generation Process in Active Suspension Control Formulation

In this paper, the dynamic behavior of hydraulic, quarter car suspensions are investigated by using linear models. These linear models include the sprung and unsprung masses with a linear visco-elastic model of the tire as well as a hydraulic cylinder and two stage electro-hydraulic servovalve model. Using a reduced order linear model, the active suspension control problem is addressed using linear optimal control. Specifically, the linear quadratic regulator formulation is used to formulate a closed loop control strategy for the suspension with the force generation process considered. Results show that the force generation process is dynamically coupled with the suspension system and should be considered when formulating the control strategy.