Real time canopy density validation using ultrasonic envelope signals and point quadrat analysis

- We develop a non-expensive system to estimate the crop density using ultrasound sensors.
- Results show that the signal obtained is highly correlated with the PQA.
- Results show that the system has to be calibrated.
- Results show that the system has a small error (4.76%) during most of the season.

An important goal for orchard and vineyard spraying systems is real-time adjustment of the operating parameters according to the target density, with the aim of keeping the droplets in the canopy, thus improving spray deposition and reducing spray drift. One apple orchard and two vineyards were scanned weekly using an ultrasonic system, the data provided by the sensors was correlated with the data obtained performing Point Quadrat Analysis. Results show the system has to be calibrated for each plant or variety and proved that the ultrasonic system is capable of sensing density within an average error of 4.76% during early, mid-season and full canopy, up to harvest date.