A Research Of Variable-Rate Fertilization Controlling System Based On GPS/DR Integration Positioning Technology

In China, precision variable-rate fertilization should be put into effect to solve the problems of a low utilization rate in fertilizer application and serious environmental pollution problems caused by the fertilizer. There are many achievements and progress made in the field of variable-rate fertilization controlling system both at home and abroad. Despite a good performance of the foreign system, its overall cost is very high and not suitable for China's domestic promotion for being affected by soil environment, while the domestic variable-rate fertilization system is characterized by complicated machinery and a high cost.In this case, the paper explores a real-time automatic variable-rate fertilization system with a low cost, based on dead reckoning and GPS integration positioning technology. It introduces the positioning technology and the design of controlling system in detail, which is divided into four parts.1. It makes an analysis of the current agricultural situation and fertilization in China, discusses the importance of variable-rate fertilization and elaborates on the significance of developing the variable-rate fertilization system.2. In order to improve the positioning accuracy, Kalman filter algorithm is designed particularly for the system to achieve data fusion through the analysis of domestic and foreign vehicle positioning methods.3. The embedded computer system is connected with fertilization devices, speed sensors, gyroscopes and hardware of GPS receiver. The integrated system can be installed in the fertilizer to complete the construction of hardware platform.4. The applications are designed to achieve real-time control of the fertilizer device, and save and display the fertilization data. In particular, for the plots that can not be fertilized once, it is necessary to store the data to ensure the accuracy in the next operation and also to prevent the data loss in case of a sudden blackout.The designed variable-rate fertilizer controlling system is featured by reliability, versatility and adaptability. It has a simple structure and a friendly interface, easy to expand and operate.This paper is a tentative analysis of combining integration positioning technology with variable- rate fertilizer technology. The problems during the research and all kinds of data obtained in the experiment have laid a solid foundation for the further study.