摘要
针对稻麦联合收割机在收获作业时难以对小麦、水稻等谷物的含水率进行准确在线测量的问题,该文基于微波反射法研究了谷物含水率在线检测方法,建立了稻麦含水率检测模型,研发了一种稻麦联合收割机谷物含水率在线检测装置。该装置采用微波测量模块对稻麦含水率进行非接触式测量,设计了电压转换电路将微波参数转换成电压信号,采用滑动平均滤波算法进行信号滤波,最后通过标定试验所建立的含水率检测模型进行稻麦含水率计算,计算结果经CAN总线通讯在显示器上实时显示。基于上述理论研究、技术开发和结构设计对所研制的谷物含水率在线检测装置分别进行了室内静态试验和田间收割试验研究,试验结果表明:检测装置的对稻麦含水率的测量范围为14%~34%,在室内静态试验和田间收割试验中的性能标准差分别为0.4583%和1.0780%,相对误差分别在2.5%和5%左右,具有良好的准确性与实用性。
Moisture content is one of the important indicators in grain harvesting,trading,storage and processing.High moisture content will lead to a series of problems of grain such as mildew,deterioration,shortened storage time,lower transaction price and higher processing cost.With the development of precision agriculture,accurate detection of grain moisture content can also accurately assess the growing situation of crops,and then provide guidance for the next season’s crop planting.Compared with the drying method,the capacitance method and the electric resistance method,the microwave method is easy to realize the non-destructive measurement of the grain moisture content,which is an important direction of moisture content detection.In the field of on-line detection of moisture content of rice and wheat in combine harvesters,foreign related research started earlier,and enterprises have commercialized,but this technology is still in the research stage in China.Aiming at the problem that the rice-wheat combine harvester is difficult to accurately measure the moisture content of wheat and rice during harvesting operation,this paper studied a non-destructive on-line detection method of grain moisture content based on microwave reflection method,established the grain moisture content measurement model,designed a non-destructive on-line detection device for grain moisture content used on rice-wheat combine harvesters.The device used a 450 MHz microwave measurement module to measure the moisture content of rice and wheat non-destructively.The voltage conversion circuit was designed to convert microwave parameters into voltage signals,and the average filtering algorithm was used for signal filtering to reduce the impact of interference factors.Finally,the moisture content detection model of rice and wheat,which was established by the calibration experiment,was used to calculate the moisture content.The calculation result was displayed on the display in real time via CAN bus communication.Due to the insufficient installation space in rice-wheat combine harvester,the structure of the detecting device was designed and optimized,and the circuit portion and the sampling mechanism were integrated in a compact structure.Based on the above theoretical research,technology development and structural design,this paper carried out laboratory static experiments and field harvesting experiments.The laboratory static experiment used rice and wheat to illustrate the establishment process of the grain moisture content detection model:30 groups of rice and 30 groups of wheat samples were prepared,moisture contents and voltages calibration experiment was completed,the rice and wheat moisture content detection models was established and the experimental results were analyzed.The field harvesting experiment was verified the practicability and reliability of the grain moisture content detecting device with rice as the test object.The experiment results show that the performance standard deviations of the laboratory static experiment and the field harvest experiment are 0.4583% and 1.0780%,respectively,and the relative error are around 2.5% and 5%,respectively.Moisture content measuring range of the detection device for rice and wheat is 14%-34%,which meets the project requirements.
作者
张伟
杨刚
雷军波
刘成良
陶建峰
覃程锦
Zhang Wei;Yang Gang;Lei Junbo;Liu Chengliang;Tao Jianfeng;Qin Chengjin(School of Mechanical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2019年第23期21-28,共8页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家重点研发计划(2016YFD0702001)
国家重点研发计划(2016YFD0700105)
上海市科学技术委员会科研计划项目(16391903102)
关键词
含水率
农业机械
微波
滑动平均滤波
试验研究
moisture content
agricultural machinery
microwave
sliding average filtering
experimental study
作者简介
张伟,博士生,主要从事智能农业装备研究。Email:zhang_wei@sjtu.edu.cn;通信作者:雷军波,助理研究员,主要从事智能农业装备研究。Email:jblei@sjtu.edu.cn。
