Optimal Design and Experiment of Picking End-effector for Spheroid Fruits Based on Stable Grasping

doi:10.3901/JME.260090

Abstract

Abstract: The stable gripping of the end-effector is one of the key technologies for the precise and reliable operation of the picking robot. However, in the agricultural unstructured growth environment, the fruit varies in size and shape, which is a major challenge for the stable gripping of the end-effector. Aiming at the stable gripping problem of spherical fruit, a three-finger two-knuckle end-effector driven by linkage is optimized. Firstly, the basic structure and parameters of the end-effector are designed, and then the forward kinematics model of the two-knuckle finger mechanism is established. Based on the stability of the fruit envelope, the multi-objective optimization objective function and constraint conditions for stable clamping are established, and the NSGA-II algorithm is used to optimize the parameters. The correctness of the motion law of the designed end-effector is verified by ADAMS simulation platform. Finally, the stable gripping test of tomato fruits with different sizes and postures is carried out. The experimental results show that when tomato fruits with different sizes and shapes are clamped, the average centroid offset of the fruit relative to the end-effector is 4.30 mm. The average position change of each knucklegrip contact point was 6.23 mm. The designed end-effector has good adaptability to different sizes and postures of tomatoes, and can effectively improve the gripping stability of the end-effector, which has important theoretical and technical support for the development and application of the picking robot.

Key words: stable gripping, fruit picking, multi-objective optimization, NSGA-II algorithm, end-effector, parameter optimization

CLC Number:

TP242

TAN Li, YU Huang, DU Xiaoqiang, HE Leiying, MA Zenghong. Optimal Design and Experiment of Picking End-effector for Spheroid Fruits Based on Stable Grasping[J]. Journal of Mechanical Engineering, 2026, 62(3): 353-365.

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