A simulation study on the use of co-state variables as strategic setpoints for tomato greenhouses. (2015)

• Record Type: Journal Article
• Authors: Linker, Raphael; Lousky, Marc
• Is Part Of: International journal of sustainable agricultural management and informatics. Volume 1:Number 2(2015)
• Page Start: 163
• Page End: 177
• Publication Date: 2015
• Subjects: TOMGRO -- optimal control -- greenhouse climate control -- simulation -- co-state variables -- tomato greenhouses -- control actuators -- target yield; Sustainable agriculture -- Management -- Periodicals; Sustainable agriculture -- Data processing -- Periodicals; Agricultural productivity -- Management -- Periodicals; Agricultural productivity -- Data processing -- Periodicals; Agricultural resources -- Data processing -- Periodicals; Agricultural systems -- Management -- Periodicals; Agricultural systems -- Data processing -- Periodicals; 338.1
• Languages: English
• ISSNs: 2054-5819

Abstract

Modern greenhouses include a large number of control actuators. Such a situation leads to the question of how to divide the control effort between these actuators. This question can be answered using optimal control theory and more particularly the system co-states. By modifying the value of these co-states the grower can control the greenhouse climate and correct deviations due to imperfect modelling or unexpected weather. This work presents a simulation study of this concept for a greenhouse with a tomato crop. For the specific scenarios investigated, by adjusting the co-state two to five times during the season, it was possible to maintain the yield within 6% of its target value. The control costs were on average 10% higher than the control costs that could be achieved if perfect weather forecasts were available at the beginning of the season.