Energy Efficient Design of a Pasture Sensor Network

The use of animals, specially ovines, for controlling infesting species in crops is an ancient method that has several advantages with respect to the use of chemical and/or mechanical techniques. Shepherds required to supervise animals, are getting increasingly less available and are costly. Over the last years, technologies for automatic animal supervision have been investigated, typically including devices to carry out localization, apply stimulus to the animals and, in some cases, report health data. Ovines have a relatively small size, which constrains the maximum weight that they can carry on, and consequently, imply that a practical system must be highly energy-efficient, to allow building light and small devices with enough autonomy. This paper presents a new system for sheep grazing control, developed in the scope of the SheepIT project. The focus of the paper is on the global communication architecture, which is a fundamental aspect for the overall system efficiency. The paper also includes simulation and experimental results that address the scalability and energy consumption aspects of the system.