Zhijun Meng

Systematic Random Deployment for Wireless Sensor Network in Agricultural Sampling-Interpolation Applications

Wireless sensor network can act as a distributed sampling system in precision farming applications which aim at estimating the spatiotemporal variability. Sensor nodes should be deployed referring to the communication range r c and the sampling range r s instead of the sensing range. In this paper, a kind of systematic random deployment based on three popular regular patterns-equilateral triangle, square and hexagon is explored to achieve both coverage and connectivity. The efficiency of different regular patterns of systematic random deployment is also compared, thus enabling to make a better deployment decision for different values of r c /r s .

Geo-referenced Spatial Multimedia Application for Agricultural Resource Management

Agricultural resource management is one of important technologies in agricultural application. The new technology, geo-referenced spatial multimedia has revolutionized the data collection, storage, management and display for agricultural resource management. This paper presents geo-referenced spatial multimedia technology including the system architecture, data collection procedures and data processing based on VMS system of Red Hen Company, and then introduced the application for agricultural resource management. Liu, H., Liu, G. and Meng, Z., 2008, in IFIP International Federation for Information Processing, Volume 259; Computer and Computing Technologies in Agriculture, Vol. 2; Daoliang Li; (Boston: Springer),

Design of Can-based Variable Rate Fertilizer Control System

A novel control system for variable rate fertilizer application based on CAN bus is the integrated application of GPS, RS, GIS and automatic control important fields in research of agriculture science. Precision Agriculture Huang, W., Meng, Z., Chen, L. and Zhao, C., 2008, in IFIP International Federation for Information Processing, Volume 259; Computer and Computing Technologies in Agriculture, Vol. 2; Daoliang Li; (Boston: Springer), pp. 1317–1320. effectiveness (Wang 1995). As an important part of precision agriculture technology, much attention has been paid to the variable rate technology. Variable rate application has the potential to improve fertilizer utilization efficiency, increase economic returns and reduce environmental impacts. Today, developed countries have used variable rate technology widely, but it is still in the starting stage in China. The rapid development of precision agriculture has increased the need for a standardized electronics communications protocol also (Marvin L. Stone et al., 2004). In this paper, we present a novel system based on CAN bus and provide evaluation experiments for the variable rate fertilizer application. The system structure consisting of the electro-hydraulic proportional valve control system, ground speed sampling ECU and light-bar guidance ECU is presented in this paper. The design of variable rate controller based on DSP and the closed loop control circuit based on proportional valve is discussed in details. Experimental results indicate that the control system can be used for variable rate fertilizer application based on CAN bus. Moreover, the system is open, easy to expand and communicate with other CAN bus based components. It also provides basis for other variable rate applications using CAN bus in precision agriculture. 2. MATIERIALS AND METHOD

Development of DGPS Guidance System for Agricultural Machinery

The purpose of this research was to develop a kind of light bar parallel guidance system based on DGPS for small agriculture machinery. This system consists of field computer, light bar and DGPS. The field computer is developed using PC/104 CPU module, running on which the embedded realtime operation system was customized by a special development tool. Single chip and CAN controller was selected for guidance light bar design, which use a row of indicator LEDs to guide drivers. Field computer and guidance light bar communicate with each other by using CAN bus. The guidance software running on the field computer was designed in object-oriented manner by integrating embedded GIS development kit. Field-testing and experiments have been done to evaluate the accuracy of the system with Trimble AgGPS 132 under different speeds, application width and light bar sensitivity, and the average of offline distance was 0.4517 meter. Results show this kind of guidance system is suitable for small-size machinery and can meet the need for parallel swath guidance for different kinds of field operation. DGPS, Agricultural Machinery, parallel guidance