REVISTA DE INVESTIGACIÓN CIENTÍFICA DE LA UNF (Año 02 - N° 01 - Marzo 2023)

Abstract

The present work is a continuation of the first versions of Sliding Mode Controllers for soil moisture modeled by nonlinear parabolic partial differential equation (2021) in which the effects of weightlessness were not considered. Sliding Mode Control (SMC) is applied to regulate the water content in the soil for precision irrigation. The dynamics of water infiltration in porous media (soil) is modeled by the Richards equation, which is a nonlinear parabolic partial differential equation (PDE) including weightlessness effects, with examples from Moon and Mars environments. Two control objectives are considered: control of average moisture and control of soil water content at a specific depth with examples from Lunar and Mars environments. SMC strategies are proposed, highlighting the use of a controller with proportional and integral actions connected in cascade for the case of sensor and actuator not placed. The simulation results indicate the excellent performance of these control systems and the rejection of external disturbances such as water evaporation, rain or weightless environments.