Abstract: Aiming at the problems of carrot harvester such as high carrot damage rate and poor rootstem separation effect, a pulltype carrot rootstem separation test bench driven by servo motor was designed. The BoxBehnken experimental design with three factors and three levels was performed, parameters such as the acceleration of pullrod, rotation speed of active disc and Angle between pullrod and conveyor belt were selected as independent variables, and the success rate and damage rate of carrot root and stem separation were taken as response values. Furthermore, the mathematical model was established, and the main reasons that affected carrot rootstem separation were analyzed as well. The results showed that the motion characteristics of pullrod had a significant influence on the separation effect of carrot rhizomes. Meanwhile, the optimal motion parameters of carrot rootstem separation mechanism were obtained as follows: the rotation speed of pullrod driving disk was 158r/min, the acceleration of pullrod was 0m/s2, and the included angle between pullrod and conveyor belt was 48°. The experimental results showed that the success rate of carrot rootstem separation was 96.2% and the damage rate was 5.2% under the optimized working parameters, which could provide a reference for improving the pulltype carrot harvester.

Key words: parameter optimization, carrot, rootstem separation, response surface method, harvesting machinery

摘要： 针对拉拽式胡萝卜收获机存在胡萝卜损伤率高、根茎分离效果差等问题，设计基于伺服电动机驱动的拉拽式胡萝卜根茎分离试验台。以驱动圆盘转速、拉拽杆运动加速度、拉拽杆与输送带夹角为试验因素，以胡萝卜根茎分离成功率和胡萝卜损伤率为响应值，利用 DesignExpert 8.0软件，采用BoxBehnken试验法设计三因素三水平试验，分别建立各因素与胡萝卜根茎分离成功率和胡萝卜损伤率的回归数学模型。结果表明，胡萝卜根茎分离机构参数对根茎分离效果影响显著，同时得到胡萝卜根茎分离机构最佳参数：驱动圆盘转速为158r/min、拉拽杆运动加速度为0m/s2、拉拽杆与输送带夹角为48°。胡萝卜根茎分离试验表明，在优化后的工作参数下，胡萝卜根茎分离成功率为96.2%，胡萝卜损伤率为5.2%，可为改进拉拽式胡萝卜收获机提供参考。

关键词: 参数优化, 胡萝卜, 根茎分离, 响应面法, 收获机械