Design Of The Monitoring System On Harvester Based On GPS And GPRS

Precision agriculture is the main direction of agricultural development in the 21 st century, and it has become a hot area of research in agricultural science and technology. It is supported by information technology. It implements operation of modern farming technology and management systems according to spatial variability, location, timing, quantity. According to the soil conditions of crop growth, production information, etc, it means regulating the fertilizer input and the density of planting, in order to improve the efficient of productivity. GPS is the main method of timing and location.The GPS receiver in the market using in the precision agricultural almost is a finished product, which is a real time RTK system and its data communication linker between master and slave is radio station. Although the finished product of GPS receiver could reach a high precise, the price is too high to afford by normal users ,while the radio station is influenced easily by weather, geographical environment or other natural factors as the data linker. It is proposed a solution that could use GPS-OEM to further development in this thesis. Make lots of experiments during the detailed comparison of the location precision and it improves the stability and valid distance by using the GPRS module as the data linker. The low cost and good extension of the system possesses a lot of users.Combined with the MCU and GPS/GPRS, a real time monitored system is designed which can monitor the harvester area data(including longitude latitude, elevation, time and production, etc). The MCU system received location information by GPS-OEM board, communicated with other system on the harvester, and collected lots of location data, then formatted the data to save to the SD card, at the same time it sent the data to the net which connected to monitor center by GPRS module and by this wireless net the monitored device and the remote control center could communicated with each other. So the monitor center could analyze the data which sent back by the MCU to plot the track of the harvester and the production distribution. The remote control center could analyze the area device to indicate the producing. The system adopts dual cores control which composed of STC89C58RD+ and STC12C4052. The HC12 GPS-OEM board of Beijing Hezhong Sizhuang company is the data collecting module. The M23 GPRS wireless module of BenQ company is the wireless data linker. The system adopts the CAN bus as the solution of communication on vehicle and SD card as the data storage solution. The system uses friendly, simplified man-machine interface to realize the gains of the remote monitoring function machine. Check the OEM board precision by comparative RTK GPS of the Trimble and HC12 GPS-OEM in this thesis.This system makes the location test to check the theory right and the control system feasible. The result of experiment has indicated that monitor system possesses the characters of operation easily and high precision.