DYNAMICS OF UNSYMMETRIC SUSPENSION TRUCKS WITH SEMIACTIVE CONTROL

This paper presents dynamic characteristics of unsymmetric suspension trucks with semi-active control to achieve compatibility between high speed stability and curving performance. According to the direction of vehicle motion, the primary longitudinal stiffness is switched so that the interwheelset structure is asymmetric fore-and-aft. Unsteady state curving behavior of the proposed unsymmetric trucks during curve entry is calculated using full car body models with non-linear wheel profiles. These calculation results are compared with experiments. In Japan, the Central Japan Railway Company made and tested trial bogies. Experimental measurements show the lateral forces acting on wheels in curve negotiation are dramatically reduced. Consequently, from both theoretical predictions and experiments, it was verified that the proposed truck is a realistic way to solve the incompatibility between steering ability and high speed operation.