A Solenoid-Actuated Pilot Valve in a Semi-Active Damping System

Linear and nonlinear “1/4 vehicle” simulation was used to determine optimal damping ratios for roadholding and ride as functions of road excitation frequency. The results were used to define the control strategy for modulating a semi-active damping system. A fast-response valve was identified as a critical element in a prospective semi-active damping system, and a solenoid-actuated two-position pilot-valve concept was developed to implement the desired control strategy. Functional description and measured performance characteristics are presented for the semi-active valve/damper assembly, as well as for the complete semi-active system, as implemented on a passenger vehicle.