Manuel Perez Ruiz
Department of Agroforestry Engineering
University of Seville
Spain

Biography
Manuel Perez-Ruiz has expertise in precision agriculture, agricultural machinery design, GNSS/RTK technology and new systems for weed management precision agriculture technologies. He has worked for RHEA project (www.rhea-project.eu) funded by the European Commission as part of his formation at University of Davis, California Biological and Agricultural Engineering Department. He has authored 17 scientific paperspublished in SCI scientific journals as well as included in various book chapters, and has also worked for 9 years as an associate professor at University of Sevilla (Spain).

Abstract
GNSS/RTK for automated weed control in cropping systems

Co-Author: David C. Slaughter

Agriculture’s reputation for its high consumption of energy is a result of historically cheap energy. A bi-product of this has been rapid development of agriculture products. However, we have seen energy costs rising, as well as the world’s population increasing - surpassing 7 billion people, and expected to keep growing in the coming decades. Therefore, agricultural production must continue to increase while utilizing minimal amounts of resources. New legislation and societal pressures are also pushing to make food-production processes as efficient as possible.

This presentation provides a set of GNSS/RTK applications for precision weed management system. It details an interesting approach using plant-specific mechanical cultivation based on a GNSS-RTK based plant map. Dr. Slaughter and his research group at the department of Biological and Agricultural Engineering (UC Davis) have developed an automatic intra-row, automatic weeding system using cultivator knives that remove the weeds along the plant lines of transplanted processing tomato crop using GNSS-RTK based plant map obtained during transplanting operation. Field test results indicated that this GNSS-RTK based automatic weeding system did not damage any plants while performing intra-row cultivation at travel speeds of 0.8 and 1.6 km/h.

Under the RHEA project an experimental patch sprayer was designed to deliver a variable-rate application. Each nozzle was controlledindependently. A microcontroller mounted on the autonomous tractor used the GNSS-RTK position and the application rate map information to determine the orders to be sent to the boom controller. A UAV equipped with a multi-spectral camera, which is capable of acquiring multi-spectral images at the desired locations and times, was used. This technology allowed provides a variable-rate application based on weed infestation maps. Such weed-specific chemical application can reduce the amount of chemical by 24-51% thus reducing cost and protecting the environment form the harmful effect of the chemical.