Site-Specific Water and Fertilizer Application by a Wireless Valve Controller Network

Variations in plant water and nutrient demand and environmental regulations to protect water quality provide significant justification for development of site-specific irrigation and fertigation systems. We have developed wireless valve controllers that self-assemble into a mesh network. Mesh networking means that controllers pass messages to extend the effective communication range without using high power radios. Solar energy is collected with a 200 mW panel to operate each controller node without yearly battery replacement. Nine nodes were tested in a mesh network and each properly responded to commands. Measurements of battery voltage, solar panel voltage, internal temperature, and external sensors were transmitted every 10 minutes. Irrigation schedules were stored locally on each node and executed automatically. Such a network of intelligent valve controllers will allow growers in orchards, vineyards, nurseries, greenhouses, and landscapes to develop management practices that improve water and fertilizer use efficiency.