基于压力触发式油茶果振动采摘装置设计与试验

Design and Experiment of Pressure-triggered Vibration Harvesting Device for Camellia oleifera Fruits

摘要:

针对丘陵山地油茶果机械化采摘存在设备适应性差、作业效率低且采摘期与花期重叠易造成花苞损伤的问题，设计了一种基于压力触发式油茶果振动采摘装置。基于生物力学测量参数，构建油茶"果-柄-枝"复合振动数学模型，明确系统前3阶固有频率及果柄分离力机制，为振动频率等关键作业参数的确定提供理论支撑。集成FSR400型柔性薄膜压力传感器与步进电机无级变频系统，采用可伸缩多激振头，提出"接触触发、按需振动"的控制策略，实现接触状态实时感知的闭环自适应作业，有效减少无效能耗与非目标损伤。通过ADAMS刚柔耦合仿真、田间试验结合Design-Expert响应面进行参数优化，确定装置的最佳工作参数为：工作频率6.89 Hz、摆幅40.97 mm、拍打位置0.25L时，实现落果率90.043%与落花率8.171%。设计的轻量化、便携化振动采摘装置适配丘陵山地复杂作业环境，兼顾采摘效率，为丘陵山地油茶果高效机械化采收提供了新型技术方案与设备支撑。

Abstract:

Aiming at the problems of poor equipment adaptability, low operational efficiency and easy flower bud damage due to the overlap of picking period and flowering stage in the mechanized harvesting of Camellia oleifera in hilly and mountainous areas, a pressure-triggered vibratory harvesting device for Camellia oleifera was designed. Based on the parameters obtained from biomechanical measurements, a composite vibration mathematical model of the Camellia oleifera 'fruit-pedicle-branch' system was constructed, which clarified the first three natural frequencies of the system and the fruit-pedicle separation force mechanism, thus providing theoretical support for determining key operating parameters such as vibration frequency. The FSR400 flexible thin-film pressure sensor and the stepper motor-based continuously variable frequency system were integrated, a retractable multi-excitation-head structural design was adopted, and a 'contact-triggered, vibration-on-demand' control strategy was proposed to realize closed-loop adaptive operation with real-time contact state perception, which effectively reduced invalid energy consumption and non-target damage. Through ADAMS rigid-flexible coupling simulation and field experiments combined with Design-Expert response surface optimization, the optimal operating parameters of the device were determined: at a working frequency of 6.89 Hz, an amplitude of 40.97 mm and an excitation position of 0.25L, the fruit drop rate reached 90.043% and the flower bud drop rate was only 8.171%. The lightweight and portable design of the device was suitable for the complex working environment in hilly and mountainous areas, and taking into account the picking efficiency. It can provide a technical scheme and equipment support for the efficient mechanized harvesting of Camellia oleifera fruit in hilly and mountainous areas.