小麦精量播种机排种高精度检测系统设计与试验  

Design and Experiment of Precision Detecting System for Wheat-planter Seeding Quantity

作　　者：陈建国 李彦明[1] 覃程锦[1] 刘成良[1] CHEN Jianguo;LI Yanming;QIN Chengjin;LIU Chengliang(School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China)

机构地区：[1]上海交通大学机械与动力工程学院,上海200240

出　　处：《农业机械学报》2019年第1期66-74,共9页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家重点研发计划项目(2016YFD070030503;2016YFD0700505)

摘　　要：为实现小麦精量播种机播种量的精准检测,基于电容传感器设计了一套高精度小麦种子粒数检测系统。研究了小麦种子以单粒形式下落和多粒同时下落两种方式下的电容与小麦种子数目之间的关系。对于小麦种子以单粒形式下落,提出用差分动态阈值法检测小麦种子数目,试验表明检测的最大相对误差为1. 54%;对于多粒小麦种子同时下落,排种轮转速从20 r/min到55 r/min,每增加5 r/min,分别建立小麦种子数目与电容积分值之间的最小二乘回归模型。试验结果表明,根据实际转速和速度最近原则选择相应的回归模型,该系统对不同的排种转速均具有较高的检测精度,相对误差介于-2. 16%～2. 23%之间。对于小麦精量播种机不同的排种模式或不同的排种速度,所设计的排种检测系统均有较高的检测精度。The precision detection of wheat-planter seeding quantity is the key of the automation control and the foundation of realizing precise seeding. Currently, existing seeding detection methods mainly include photoelectric-based methods, image-based methods and capacitance-based methods. For the photoelectric-based method, the detection accuracy of photoelectric sensor is affected by the vibration, light, temperature and other factors on the farmland. For the image-based method, its high precision detection provides a new way to improve the performance of wheat-planter seeding. However, image processing technology requires special equipment with high cost, and cameras are easy to be interfered by external light. Consequently, it is difficult to be widely applied in the complex environment on the farmland. Compared with photoelectric-based and image-based methods, the capacitance-based method is less affected by light and dust and thus has a strong environmental adaptability. Aimed at the problem of precision detection of wheat-planter seeding quantity, a precise detecting system for wheat-planter seeding quantity was developed based on the capacitance sensor. The corresponding parallel plates were designed to improve the detecting accuracy of the capacitance sensor. Then, the relationship between capacitance value and the quantity of wheat seeds under two modes of single-seed falling and several-seed falling was investigated in detail. For the mode of single-seed falling, a differential dynamic threshold method was proposed to detect the number of wheat seeds. The experiment results indicated that the maximum relative error was 1.54%. For the mode of several-seed falling, the least squares regression model between wheat seeds quantity and capacitance integral value was established at interval of 5 r/min ranged from 20 r/min to 55 r/min. The experiment results showed that according to the principle of the actual speed and the closest speed to select the corresponding regression model,the system had high detection accu

关 键 词：小麦播种机 播种量 电容传感器 差分动态阈值法 最小二乘法 

分 类 号：S126[农业科学—农业基础科学] S223.2