Dynamic behaviour of rack vehicle considering traction characteristics in mountainous region

The traction drive system is critical to the power performance and safety of rack vehicles operating on steep mountain grades. Currently, research on the traction drive systems of rack vehicle is limited, and few studies consider the traction characteristic curve. To address this issue, a coupled dynamics model of rack vehicle is established, incorporating the engagement behavior of the traction drive system and the traction characteristic curve, based on vehicle-track coupled dynamics theory and gear dynamics theory. The impact of different traction characteristics on the dynamic performance of rack vehicle in mountainous areas is investigated. Results indicate that increasing starting torque amplifies gear and car-body vibrations. Raising the turning-point speed prolongs strong excitation and increases meshing frequency, elevating car-body vertical acceleration and the wheel-load reduction rate. Under traction, the slip ratio rises, the sliding area expands, and operational safety degrades. A traction strategy balancing power, safety, and ride comfort is proposed.