Optimization Design and Testing of the Under‐Actuated Lotus Seedpod Harvesting Grasping Mechanism

ABSTRACT To address the high labor intensity and low efficiency associated with traditional manual lotus seedpod harvesting, this study proposes the design of an under‐actuated, three‐finger linkage grasping mechanism that mimics the grasping motion of the human hand. The design is based on the physical properties of the lotus seedpod, ensuring a compact structure and ease of control. Kinematic and static models of the grasping mechanism were developed, and the range of structural parameters was determined using custom‐developed software. Additionally, genetic algorithms were employed to optimize these parameters. The Denavit‐Hartenberg (D‐H) parameter method was used to analyze the working space of the grasping mechanism, and virtual motion simulations confirmed the rationality and accuracy of the mechanism design. A prototype of the lotus seedpod harvesting grasping mechanism was developed, and a harvesting test platform was constructed to conduct simulated harvesting experiments in a laboratory environment. The experimental results indicate that the grasping mechanism requires an average of 5.34 s to harvest a lotus seedpod, with an enveloping success rate of 95% and a cutting success rate of 80%. These results demonstrate the promising application potential of the proposed grasping mechanism in lotus seedpod harvesting. This study provides a theoretical foundation and practical roadmap for the mechanization and automation of harvesting lotus seedpods and similar fruits and vegetables.