Hunting Stability Enhancement of a Train Bogie Employing Inerter‐Based Suspension Mechanism

The bogie hunting instability may occur in the train traveling process, which has an important effect on the train operation safety and passenger ride quality. Three inerter‐based suspension mechanisms are designed and applied in the secondary lateral suspension of the train bogie to improve bogie hunting stability. The M1 and M2 configurations consist of a spring, an inerter, and a damper, while M3 configuration adds an additional auxiliary spring. The dynamic model of train bogie employing inerter‐based suspension mechanism is established, and the bogie critical speed and limit cycle oscillation (LCO) amplitude are acquired based on the bifurcation analysis method and also compared with those of the original suspension. The structural parameter analysis of inerter‐based suspension mechanism is conducted, and the structural parameters are optimized using the nondominated sorting whale optimization algorithm (NSWOA). The results show that M1 and M2 configurations worsen the bogie hunting stability, while the M3 configuration enhances the bogie hunting stability, in which the linear and nonlinear critical speeds are larger than those of the original suspension, and the LCO amplitude of the bogie lateral motion is smaller. Choosing larger values of secondary suspension lateral stiffness, auxiliary spring stiffness, and inertance of the inerter can increase the linear and nonlinear critical speeds. Furthermore, the optimized M3 configuration using the NSWOA obtains the best bogie hunting stability performance, which has larger linear and nonlinear critical speeds than those of the original suspension and unoptimized M3 configuration, and the LCO amplitude of the bogie lateral motion is also smaller. Thus, the inerter‐based suspension mechanism shows its effectiveness in suppressing the bogie hunting motion and offers valuable guidance for the train suspension design.