Optimization on kinematic characteristics and lightweight of a camellia fruit picking machine based on the Kriging surrogate model

In order to achieve fully automated picking of camellia fruit and overcome the technical difficulties of current picking machinery such as inefficient service and manual auxiliary picking, a novel multi-links-based picking machine was proposed in this paper. The working principle and process of this device was analyzed. The mechanism kinematics equation was given, and the velocity executive body was obtained, as well as the acceleration. The acceleration at pivotal positions was tested in the camellia fruit forest, and the simulated results agreed well with the experimental ones. Then, the maximum acceleration of executive body and weight was considered as the optimization objective, and the rotating speed of crank, the radius and thickness of crank and the length and radius of link rod were regarded as the design variable. Based on the Kriging surrogate model, the relationship between variables and optimization objectives was built, and their interrelations were analyzed. Finally, the optimal solution was acquired by the non-dominated sorting genetic algorithm II, which resulted in the reduction of the maximum acceleration of executive body by 31.30%, as well as decrease of weight by 27.51%.