Design and experiment of transfer and loading machine for tobacco poles in bulk curing barn scenario

Tobacco leaf curing is a critical stage in the tobacco processing chain, and its operational methods and equipment technology levels are key factors affecting leaf quality, operational efficiency, and overall economic benefits. However, current curing practices are still dominated by manual operations, which are generally characterized by high labor intensity, low efficiency, high labor costs, and insufficient operational safety. These limitations hinder the large-scale, standardized, and efficient development of the tobacco curing process. To address these challenges, this study designed and developed a tobacco pole transfer and loading machine specifically for dense curing barn environments, based on the structural characteristics of dense curing barns and the technological requirements of tobacco pole loading. The proposed machine adopts a multi-stage lifting system combining a five-stage mast, servo motors, and ball screws, enabling precise vertical lifting within a range of 1.3~3.6 m. A reciprocating tobacco pole carrying mechanism, driven by staggered linear modules, allows adjustable pole inclination within a range of 0~32°, effectively avoiding interference with curing barn walls. Finite element analysis of key components indicates that the strength of major load-bearing structures, including the powered chassis and lifting mast, meets safety requirements. The natural frequencies of mast stages 1 to 6 range from 63.92 to 354.00 Hz, avoiding resonance during operation. In addition, the safety factor of the tobacco pole carrying blade is significantly higher than the allowable value, satisfying fatigue life design criteria. Field experiments conducted in tobacco-producing areas demonstrate that the loading success rate of the developed machine exceeds 90%, and operational efficiency is improved by approximately 3 to 5 times compared with traditional manual methods. The results confirm that the proposed tobacco pole transfer and loading machine can effectively accomplish pole transportation and hanging tasks in dense curing barns, substantially improving curing operation efficiency.