Research on hunting motion of independent wheel bogie based on scale model

The independent wheel can rotate freely around the axle, and the rigid coupling between the wheels and axles is released, leading to the disappearance of the longitudinal creep force of the wheel tracks. The wheel-axle system is difficult to be automatically aligned in a straight line, and its guiding problem needs to be solved urgently. This paper applies the MacPherson suspension structure to the independent wheel bogies, and uses similar theory to demonstrate the feasibility of the scale model. A 1/20 scale model of the independent wheel bogie with an“V”shaped tilted rotation axis on the same side is established, a prototype is built for linear operation test, and the dynamic simulation of the full-scale bogie model is carried out. The results show that the new independent wheel bogie can reproduce the hunting motion phenomenon in a straight line, and the simulation results are consistent with the scalability testing results. With the increase of the running speed, the hunting motion of the independent wheelset becomes increasingly intense. Installing a transverse spring with a stiffness of 7.5 MN/m in the axle system can reduce the amplitude and frequency of the front axle transverse motion for bogie by 72% and 79%, respectively. By adjusting a series of suspension parameters and the lateral spring stiffness, the bogie can be automatically aligned in a straight line.