The Wavelength of Hunting Motion of a Soft Truck

Abstract

The wavelength of hunting motion is one of basic quantities expressing the hunting motion characteristics of a railway vehicle. Though formulae for a single wheel-set and a rigid truck are well known, they are not applicable to a soft truck, in which horizontal suspension stiffness between the axle box and truck frame is small. In this paper, an approximate expression for the wavelength of a soft truck is presented and verified with measured data.