Railway truck is necessary to have excellent curving performance as well as high speed hunting stability, but generally they are contrary to each other. "Active-bogie-steering (ABS) Bogie", is one of the methods to realize the compatibility between curving performance and hunting stability. ABS bogie has active steering mechanism only between car body and, bogie frame, and bogie frame is steered by actuators toward "radial steering position", which realizes no "bogie angle shortage". In this paper, the actuator consists of AC servo controlled motor and mechanism with friction is modeled to realize ideal response and tracking ability for desired actuator force. The effective control which compensates actuator friction is proposed and is investigated in experiment. Moreover, calculation of hunting stability for ABS truck by using half body model was compared with other truck model.
