Abstract
In this paper will be presented an alternative of feed forward controller (FFC) system to overcome four wheel steering weaknesses. The system estimates vehicle output parameters that consists of lateral acceleration (v ), roll rate (è ) and yaw rate (ϕ ) as well as the correct input parameters of vehicle that consists of longitudinal speed (Uo) and steering wheel (sw). To estimate vehicle output parameters will be used full car mathematical model. The estimated vehicle output parameters together with given vehicle input parameters are used to estimate understeer coefficient (Ku). Finally, it will be used to compute the correct vehicle input parameters those are required by the 4WS system.