Capacitive sensor to estimate plant protection products sprayed in precision agriculture applications

The evaluation of the distribution of plant protection products sprayed on the leaves of a plants or trees is a key element for optimizing their usage. While various methods exist for assessing this deposition, they are currently costly to implement, both in terms of the technique itself and the time required for measurement. In the research for alternatives, a low-cost capacitance sensor emerges as an attractive system solution for measuring the accumulation of water with pesticides on leaves and its distribution throughout the plant. In this work, the design of the sensor system is presented, and the accuracy, the main static and dynamic characteristics estimated and performance under different conditions. The designed system enables the measurement of concentrations ranging from 0 µL to 60 µL with a resolution better than 0.1 µL.