自主调平辣椒整枝打杈机构设计与试验

Design and Experiment of Self Leveling and Pruning Mechanism for Chili Pepper

摘要:

目前在辣椒移栽、果实收获等领域已有相关机械化产品，但对能够实现辣椒果实增产增收的整枝打杈环节仍需人工操作。结合辣椒种植环境的多样化，本文设计了一种能够实现自主调平、切削侧枝的辣椒整枝打杈机构，并对其调平控制方法进行了研究。根据辣椒整枝打杈农艺，设计了对辊式离心多刀整枝打杈末端执行器。利用EDEM软件建立了辣椒植株的柔性体离散元模型，进行了对辊式离心多刀整枝打杈末端与植株的互作仿真试验。选取进给速度、打杈机构倾角、辊子转速 3个对打杈性能影响较大的参数进行了正交试验分析，最终得到整枝打杈末端的最优参数组合：为进给速度 1.5 m/s、打杈机构倾角15°、辊子转速1187r/min。设计了整枝打杈末端自主调平机构，利用ADAMS软件对所设计的调平机构进行动力学仿真。提出了基于模糊PID的调平控制方法，利用Matlab/Simulink仿真模块对比了传统PID算法与模糊PID算法的响应速度。最后，搭建了辣椒整枝打杈样机，进行了田间试验。试验结果表明，当作业速度为 1.5 m/s时，侧枝切除率达到86.3%，辣椒植株损伤率控制在 6.7% 以内，最终辣椒打杈成功率为 76.7%，验证了本文所设计的辣椒整枝打杈机构的可行性。

Abstract:

Currently, there are mechanized products available for pepper transplanting and harvesting, but manual operations are still required for pruning, which is crucial for increasing pepper yield. Considering the diverse planting environments for peppers, a self-leveling pepper pruning machine was designed and its leveling control system was developed. Based on the agricultural practice of pepper pruning, an end-effector for pruning was designed and its working principle was introduced. The flexible-body discrete element model of pepper plants was established by using EDEM software to simulate the interaction between the end-effector and the plant.Orthogonal experimental analysis was performed by selecting three parameters, namely feed speed，end-effector tilt angle, and roller speed, which had a significant impact on the pruning performance.The optimal parameter combination for the end-effector was determined as follows：feed speed was 1.5 m/s, end-effector tilt angle was 15°, and roller speed was 1 187 r/min. To meet the requirements of operating in complex hilly terrain, a dual-axis leveling mechanism was designed and its working principle was introduced. Dynamic simulation of the designed leveling mechanism was conducted in ADAMS, providing reference for the selection of the driving components. Simultaneously, the leveling control algorithm was determined, and the response speed of the traditional PID algorithm was compared with the fuzzy PID algorithm by using the Matlab/Simulink simulation module. Finally，a prototype of pepper pruning was built and field experiments were conducted. The experimental results showed that at a working speed of 1.5 m/s, the lateral branch cutting rate reached 86.3%, the pepper plant damage rate was controlled within 6.7%, and the final success rate of pepper branching was 76.7%, verifying the feasibility of the designed pepper pruning mechanism.