Analysis on vertical–pitch coupled dynamics characteristics of shearer with corrected load

With regard to the severe vertical and pitching vibration of shearer in actual working conditions, the vertical–pitch coupled dynamics model of shearer with 13 degrees of freedom was established using multi-body dynamics theory. Based on the elasticity theory, Hertz contact and collision dynamics, the connection stiffness model of shear body and the traction section, the rocker arm with clearance and the traction section, the support stiffness models for the guide shoe and the smooth shoe, and the stiffness characteristics model of the rocker arm were constructed respectively. Taking into account the convergence of solution process and the reliability of results, a modified drum load was proposed as the external excitation of the system and the dynamic characteristics of key parts of shearer under different working conditions were analyzed. The numerical models were validated against the vibration responses of the whole machine and critical components of shearer obtained from mechanical test under different operating conditions. The research results provide theoretical basis for the structure optimization and process parameter optimization of shearer.