Investigation on the Impact of Unilateral Step Load on the Torsional Vibration Characteristics of Tracked Vehicle Electro-Mechanical Transmission System

With the increasing demand for environmental protection and sustainable development, tracked vehicles with Electro-Mechanical Transmissions (EMT) have garnered significant attention due to their compact size, high efficiency, and large power transmission capabilities. However, existing re-search often overlooks the differences in resistance and motion states experienced by both tracks, leading to a lack of alignment between the exploration of EMT characteristics and vibration suppression strategies with real-world conditions. This paper investigates the torsional vibration characteristics of electric tracked vehicle EMT under unilateral load step-change conditions. A dynamic model of EMT torsional vibration was established to explore the impact of unilateral load resistance torque step changes on the torsional vibration characteristics of EMT during steady-state travel. The study found that under the influence of unilateral load step changes, the energy balance of the system's inertial loads is disrupted, triggering transient torsional vibrations in the unilateral flexible drive system, dominated by low-order modes. Meanwhile, the vibrational energy on both sides flows back and forth through the coupling points, causing an imbalanced distribution of vibrational energy and further exacerbating the irregular oscillation of the system's torque.