Parametric simulation study of traction curving of three axle steering bogie designs

The development of self-steering bogies in locomotives has occurred without extensive study of traction curving bogie dynamics. It is reported that these bogies are unable to steer at high tractive effort levels with the performance essentially the same as rigid bogies. This is due to the required adhesion level approaching wheel rail friction limits and causing creep saturation. Reassessment of the curve steering task in a hauling locomotive has identified that existing concepts of perfect steering [R.M. Goodall and T.X. Mei, Chapter 11: Active suspensions, in Handbook of Railway Vehicle Dynamics, S. Iwnicki, ed., Taylor & Francis Group, Boca Raton, FL, USA, 2006], [R.M. Goodall, S. Bruni, and T.X. Mei, Concepts and prospects for actively-controlled railway running gear, Vehicle Syst. Dynam. 44, supplement 1 (2006), pp. 60-70] are not appropriate for high traction loads in hauling locomotives. An extensive parametric simulation study has been conducted on steering bogie designs for hauling locomotives. Testing of passive steering bogie designs have shown superior performance from forced steering bogies where steering is only partially dependant on wheel rail creep forces. New active steering bogie designs have been proposed [S. Simson, Railway bogie, Australian Provisional Patent Application No. 2007900891, 2007] where steering control is independent of wheel rail creep forces. The new designs combine force steering of wheelsets with secondary yaw activation. The parametric study shows that new active steering bogie designs give superior steering performance under traction.