Optimal control of physiological processes of plants in a green plant factory

In a plant factory, optimal control for obtaining higher yield and better quality of plants is essential. A modern control technique using optimal regulators and an intelligent control technique using genetic algorithms were applied to the control of the physiological processes of plants. In modern control, the variation in diameter with light intensity was measured, and the ARMA model was identified using the least squares method. Optimal regulators with a Kalman filter were used to control the water status of plants. In the intelligent control, on the other hand, the neural network was used for the model identification of net photosynthetic rate as affected by intermittent drainage of a hydroponic solution, and then the genetic algorithm was used for optimization via model simulation. These control techniques were quite useful for the optimal control of the physiological processes of plants.