Precision agriculture requires the use of automation techniques to improve crop productivity through the optimization of natural resources. In order to achieve this, continuous data acquisition of environmental variables must be conducted real-time and transmitted to the proper computing devices. Data acquisition systems, such as data-loggers, are typically used with sensors and actuators to implement automated actions for precision agriculture purposes. However commercially available data-loggers do not offer enough flexibility, scalability and connectivity services. This paper presents the design and development of a modular data- Acquisition system that can be adapted to different agricultural automation requirements. A scalable design approach is considered in order to provide connectivity services at different communication levels, i.e. the same device may work in a stand-alone mode by registering the data locally, or it can interact with other computing devices by implementing small or large communication networks to produce aggregated data. Short range (wireless sensor network) and global access communication (internet) are supported by the system, so it can be configured according to the application specific needs. The proposed system has been evaluated in representative precision agriculture applications, such as closed-loop irrigation and reference evapotranspiration measurements, where experimental results are discussed.
