【摘要】 【目的】针对现有草莓采摘末端执行器夹持力控制不佳、易损伤果实或抓取不牢的问题，设计一种同时夹持果实与果梗的无损采摘末端执行器，通过连杆组与扭力弹簧控制最大夹持力，避免采摘过程中果实受损。【方法】首先，建立果实夹持机构的运动轨迹与输出力矩数学模型，设计适配的扭力弹簧参数，借助Adams软件仿真运动轨迹与接触力，利用WorkBench软件的Ls-Dyna模块分析夹持时草莓的应力与变形；其次，建立果梗夹持机构模型，求解稳定夹持与切割果梗所需的力；最后，制作样机并按果梗直径分3组开展采摘试验，对比采摘前、后果实损伤程度。【结果】结果表明，该执行器可夹持直径24～60 mm的草莓，最大接触力为0.80 N、最大应力为57 640 Pa、最大变形为0.677 mm，均在草莓耐受范围内；果梗切割最小驱动力为13.59 N，采摘成功率为95%，满足草莓无损采摘作业要求。更多还原

【Abstract】 [Objective] Aiming at the problems of inadequate clamping force control, easy fruit damage or unstable grasping of existing strawberry picking end effectors, a non-destructive picking end effector that clamps both fruit and peduncle simultaneously was designed. The maximum clamping force was controlled by a linkage assembly and a torsion spring to avoid fruit damage during picking. [Methods] Firstly, a mathematical model of the motion trajectory and output torque of the fruit clamping mechanism was established, and adaptive torsion spring parameters were designed. Adams software was used to simulate the motion trajectory and contact force, and the Ls-Dyna module of WorkBench software was utilized to analyze the stress and deformation of strawberries during clamping. Secondly, a model of the peduncle clamping mechanism was established to solve the forces required for stable clamping and peduncle cutting. Finally, a prototype was fabricated, picking tests were carried out in 3 groups according to peduncle diameter, and the fruit damage degree before and after picking was compared. [Results] The results demonstrate that the end effector can clamp strawberries with a diameter of 24-60 mm, with a maximum contact force of 0.80 N, a maximum stress of 57 640 Pa and a maximum deformation of 0.677 mm, all within the tolerance range of strawberries; the minimum driving force for peduncle cutting is 13.59 N, and the picking success rate is 95%, which meets the requirements of non-destructive strawberry picking.更多还原