Authors

Abstract

To address the challenges of labor-intensive and inefficient manual harvesting of Lycium barbarum L. grown on a double-layer trellis, this study proposes a human–robot collaborative system. The system consists of a hand-held high-frequency rocker-oscillator harvester and an electric receiving cart. Mechanical property measurements of fruits and branches revealed detachment forces of 1.2 to 1.8 N for mature fruits and 2.5 to 3.0 N for immature fruits, with an average bending elastic modulus of 548.9 MPa for fruit-bearing branches, providing a basis for selective harvesting. A Box–Behnken design was employed to optimize vibration frequency, harvesting duration, and inter-rod spacing, and response surface analysis identified the optimal parameters as 18 Hz, 4.5 s, and 26 mm. Next, a central composite design optimized the receiving cloth tilt angle and radius to maximize collection efficiency, defined as the ratio of fruits collected by the cart to the total number of detached fruits. Field validation demonstrated a mature fruit harvesting rate of 96.2%, a mis-harvesting rate of 4.3%, a damage rate of 3.7%, and a collection efficiency of 96.1%, with relative errors below 0.5% compared to model predictions. These results confirm the system’s effectiveness and provide technical support for standardized, low-damage mechanized fruit harvesting of Lycium barbarum L..

Abstract in Chinese

为解决双层篱架栽培枸杞人工采摘劳动强度大、效率低下的问题，本研究提出了一种人机协作采摘系统。该系统由手持高频摇摆振动采摘机与电动接果车组成。对果实及枝条力学特性的测定结果显示，成熟果实的脱离力为 1.2 至 1.8 N，未成熟果实为 2.5 至 3.0 N，果枝的平均弯曲弹性模量为 548.9 Mpa，为实现选择性采摘提供了理论依据。研究采用 Box–Behnken 试验设计对振动频率、采摘时长及振动杆间距进行了优化，并通过响应面分析确定最佳参数为振动频率 18 Hz、采摘时长 4.5 s以及振动杆间距 26 mm。随后，利用中心复合试验设计对接果布的倾角与半径进行了优化，以最大化接果效率，接果效率定义为接果车收集到的果实数量占脱落果实总量的比例。田间验证结果显示，成熟果实采摘率达到 96.2%，误采率为 4.3%，损伤率为 3.7%，接果效率为 96.1%，各项指标实测值与模型预测值的相对误差均低于 0.5%。上述结果表明该系统具有高效、低损伤的应用潜力，为双层篱架栽培枸杞的标准化机械化果实采摘提供了技术支撑。