为了获取区域内的玉米播种质量信息并对其进行远程监测与管理,提出了基于GPS和GPRS的远程排种监测系统。该系统利用PVDF(polyvinylidene fluoride,聚偏二氟乙烯)压电传感器实时监测指夹式排种器播种质量信息并通过GPS接收器实现了播种质量信息位置的精确定位；同时,系统通过GPRS DTU模块的应用和远程服务器软件的设计,实现了播种质量信息数据的远程传输与管理。试验结果表明,该系统播种量检测精度为97.4%,漏播检测精度为96.1%,重播检测精度为 95.9%,该系统能够有效检测玉米播种质量并具有监测数据远程监管的功能。

The information of corn sowing quality such as seeding amount, missed planting and repeated planting not only reflects the implementation effect of corn planting, but also is an important reference for accurate prediction of corn yields.It is very important to obtain the information of corn sowing quality and monitor and manage it remotely.In this paper, a remote seeding monitoring system based on GPS(global position system) and GPRS(general packet radio service) was designed.The system is mainly composed of a sensor signal acquisition unit, main control unit, DGPS(differential global positioning system), GPRS DTU(GPRS data transfer unit) module and remote server.It can monitor the seeding status of pickup finger seed metering device in real time by a PVDF(polyvinylidene fluoride) piezoelectric sensor, and achieve a precise position of the seeding status by the DGPS.The data of sowing quality can be transmitted by GPRS DTU modules and managed by remote server software.In order to improve system monitoring accuracy, the PVDF piezoelectric sensor is attached to the seeding outlet baffle with a sectorial form.The sensor is soft, thin and highly sensitive.During the process of seeding, seeds hit the PVDF piezoelectric sensor one by one.The hits of seeds make the piezoelectric polarization inside the film.The sensor generates a voltage signal respectively.Therefore, the voltage signals generated by the piezoelectric sensor can be used to determine whether there is missed planting or repeated planting.The current seeding position is recorded by DGPS which can provide better accuracy than basic GPS.The DGPS consists of 2 parts, i.e.the GPS mobile station and GPS reference station.The GPS reference station comprises a GPS receiver, a GPRS DTU module and a single chip microcomputer.The GPS mobile station is used to observe the GPS signals which are used for sowing position.The GPS reference station is used to make a correction data, which is used to reduce the deviation of sowing position.The GPS mobile station is fixed on the top of tractor and the main control unit is installed in the cab, and both of them are connected with each other by shielded wire.The GPS reference station can be placed anywhere within 10 km distance from planting site, and it is not allowed to move during the process of seeding.Another GPRS DTU module is used to transmit sowing quality data and position data from the main control unit to the remote server.A server application based on Visual Basic 6.0 and Access 2003 has been developed.The application has a powerful function and a friendly interaction interface, and it is easy to operate.By the server application, the sowing quality data can be monitored in real time and the sowing quality information can be shown in a map.The map is based on the actual percentage of missed planting and repeated planting, and there are 3 different colors to represent different information of corn sowing quality.Red represents missed planting, yellow represents repeated planting, and green represents normal.Meanwhile, the system also provides the function of query, statistical analysis, and printing reports.The system was applied for a field test.The experiment results showed that the system′s accuracy of seeding amount was 97.4%, accuracy of missed planting was 96.1% and accuracy of repeated rate was 95.9%.This system can effectively monitor seeding performance and have the function of monitoring and management for the sowing data remotely.

S232.3

“十二五”国家科技计划课题(2011BAD20B09)；长春市科技计划项目(14KG087)；吉林省教育厅“十二五”科学技术研究(201449)