并联式多采摘头红花采摘装置的设计与试验

    Design and test of parallel multi-picking head safflower picking device

    • 摘要: 针对红花机械化连续采收时难以在保证工作效率的同时兼顾较高的采净率等问题,该研究结合鲜红花果球空间分布特性设计了一种并联式多采摘头红花采摘装置。该研究以“先规整、后采摘”为核心策略,基于红花植株物理特性测定及枝条力学分析,设计了喂入集拢机构。通过理论分析与试验验证,确定其核心参数为:通道宽度200 mm、分禾板张角66°、安装高度580 mm,可以显著约束果球横向分布,形成有序采摘界面。针对规整后植株特征,设计核心采摘单体:采用三组对辊并联布局,对辊直径30 mm,间隙1.8 mm,长度300 mm,中心间距85 mm,可有效覆盖植株冠层纵向范围并避免卡滞。基于质量属性分析与运动学约束确定单体往复运动最小周期需大于2.45 s。建立机具前进速度、采摘单体往复周期、相位差耦合下的空间运动轨迹覆盖模型,揭示多采摘头通过相位差实现有效采摘范围互补、形成连续动态包络面的机理。以花丝采净率和果球漏采率为评价指标,先通过单因素试验确定各参数取值范围,再经过Box-Behnken试验优化得到最佳作业参数为相位差0.54π、往复周期2.9 s、前进速度0.46 km/h。在此参数下,花丝采净率达90.27%,果球漏采率为10.93%,满足行业标准,验证了装置的可靠性。该研究可为鲜红花机械化采收装备的发展提供参考。

       

      Abstract: Safflower is one of Xinjiang's key specialty cash crops, offering multiple values including medicinal, edible, dye, oil, and feed uses. It serves as a vital pillar for increasing local farmers' income. The harvesting of its filaments has long relied on manual labor, which is labor-intensive, costly, and plagued by seasonal labor shortages. Furthermore, fresh safflower fruit balls are characterized by their scattered spatial distribution and varying heights. Existing harvesting equipment often struggles with low efficiency, a high fruit ball miss rate, or fruit damage, making it difficult to achieve both high throughput and a satisfactory picking rate. There is, therefore, an urgent need to develop efficient and well-adapted mechanical harvesters for safflower.This study proposes a core strategy of "gathering first, picking later" and designs a parallel multi-picking-head safflower harvesting device. It aims to enhance harvesting efficiency through continuous mechanical operation and to achieve efficient, low-damage, continuous blind harvesting of fresh safflower by coordinating a feeding/gathering mechanism with multiple picking units to form a continuous dynamic envelope around the plant canopy. First, based on an analysis of the physical properties of safflower plants and the mechanics of their branches, a feeding and gathering mechanism was designed. Its key parameters were determined as a channel width of 200 mm, a divider plate angle of 66°, and an installation height of 580 mm. This configuration significantly compressed the lateral distribution width of the fruit balls by 47.62%, creating an orderly picking interface. Subsequently, a parallel picking unit centered on three sets of counter-rotating rollers was designed. The roller parameters were set as follows: diameter 30 mm, gap 1.8 mm, length 300 mm, and center distance 85 mm. Mass property analysis and kinematic constraints determined the unit's minimum reciprocating cycle to be greater than 2.45 s. A spatial motion trajectory model was established, coupling the machine's forward speed, the reciprocating cycle of the picking units, and their phase difference. This model elucidates the mechanism by which multiple picking heads, through complementary phase differences, achieve full coverage of the harvesting area and form a continuous dynamic envelope. Using the filament net picking rate and the fruit ball miss rate as evaluation metrics, single-factor tests were conducted to determine the parameter ranges. Subsequently, Box-Behnken response surface methodology was employed for optimization, yielding the optimal operational parameters: a phase difference of 0.54π, a reciprocating cycle of 2.9 s, and a forward speed of 0.46 km/h. Field validation tests under these optimal parameters resulted in a filament net picking rate of 90.27% and a fruit ball miss rate of 10.93%. The relative error between the experimental results and the model predictions was less than 5%, meeting relevant industry standards for mechanized safflower harvesting. The device features a rational structure and simple operation. By effectively integrating the gathering and multi-head coordinated picking actions, it achieves efficient continuous blind harvesting of fresh safflower. It is well-suited for large-scale cultivation in arid regions like Xinjiang and can significantly reduce labor intensity and production costs. This study provides a practical technical solution for the mechanized harvesting of fresh safflower and offers a theoretical reference and technical basis for developing harvesting equipment for similar crops.

       

    /

    返回文章
    返回