Chaotic oscillation of a wheelset rolling on rail; Verification on roller rig

This paper deals with both theoretical study and experiment on the chaotic behavior of a rolling wheelset. The main purpose of this report is to confirm the actual occurrence of the chaos in the rolling wheelset compared with numerical simulation results. In the experiment, a 1/5 scale model of one-axle truck is used. The truck rolls on rail-wheels of a roller rig. When the rolling speed increased, the scaled wheelset shows a chaotic movement accompanied with the hard collision against the rail-wheels. The collision was caused by the growing hunting motion. These responses were confirmed by the evaluation both of the maximal Lyapunov exponents and the correlation dimensions. The actual experiment showed a remarkable difference to the results of numerical simulation at higher rolling speeds. The difference emerges from a simplified model for the flange contact.