Abstract:To enhance the efficiency and reduce the working resistance of stone picking operations, a novel Archimedes spiral-shaped rake stone picker was designed and evaluated, aiming to address the limitations of conventional stone pickers. A kinematic analysis of the digging teeth during stone picking and throwing operations was conducted to determine the optimal structural and operational parameters for key components, thereby ensuring efficient stone removal and minimizing energy consumption, which are crucial factors for optimizing the stone picker’s overall performance. To validate the reliability and performance of the stone picker, a three-factor, three-level response surface experiment based on Box-Behnken design was employed to identify the optimal operating parameters that maximize stone picking efficiency and minimize operating torque. The digging teeth blade initial sliding angle, machine forward speed, and shaft rotation speed were selected as experimental factors, while stone cleaning efficiency and operating torque served as evaluation indicators. Analysis of variance (ANOVA) and response surface analysis were performed by using Design-Expert software to assess the influence of experimental factors and their interactions on the stone picker’s performance. Multi-objective optimization of the established linear regression model revealed that the optimal stone picking efficiency was achieved with a digging teeth blade initial sliding angle of 14.73°, a machine forward speed of 0.34 m/s, and a shaft rotation speed of 171.89 r/min. Field validation tests conducted with the optimized parameters demonstrated an average stone cleaning efficiency of 90.04%, meeting the requirements for efficient stone picking in agricultural fields.
