Geometry Simulation of Track Torsion-Irregularity Based on 6-DOF Platform

In order to obtain the geometry information of track torsion irregularity, an inverse kinematics model and a pose correlation model for the double 6-degree-of-freedom (DOF) platform of a track torsion irregularity simulator were established, taking into account the characteristics of torsional irregularity and the structure of the track torsional irregularity simulator. By means of Simulink inverse kinematics model, the inverse kinematics solutions for three types of torsion irregularity of domestic commonly used gauges and wheelbases of bogies were calculated. The results have a good consistency with the forward kinematics solutions, which verifies the correctness of the established inverse kinematics model and pose correlation model. In addition, taking a certain type of bogie as an example, laboratory tests were carried out using torsion irregularity of different basic lengths to study the effect of the basic length on the wheel loading reduction rate. The results show that the smaller the basic length of torsion irregularity is, the larger the wheel loading reduction rate will be. The maximum wheel loading reduction rate for 2.4 m and 5.0 m basic lengths are 0.594 and 0.581, respectively, both within the safety limit of relevant national standards.