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Nowadays, some of the most important challenges to society are focused on the use of renewable energies, mitigation of greenhouse-type gases and residual treatment. Microalgae are becoming one of the most powerful solutions to contribute to these problems. So, industrial facilities have been developed in the last decades to produce this type of microorganisms. However the dynamics of these systems is very complex, and advanced models and control strategies are required. The Interpolating Control is a novel technique with capacity to deal with state and control constraints with low computational burden, being suitable to be applied in this type of processes. This technique has been used in the literature to control simulated or laboratory scale systems. This paper shows the operation results for a Interpolated Controller in an industrial raceway photobioreactor to contribute in the control of these real processes.

The Thermal InfraRed Sensor (TIRS), an infrared (IR) radiometer developed at Centro de Astrobiología, is one the sensors that compose the Mars Environmental Dynamics Analyzer (MEDA) onboard NASA?s Mars 2020 mission. It will measure the net thermal infrared radiation, reflected solar radiation at the surface, atmosphere temperature and surface skin brightness temperature using five different channels. The present paper provides a brief description on TIRS design and channels requirements. Then, a detailed presentation of sensor model equations and a sensitivity analysis to model uncertainties are included. Finally, accuracy and resolution calculus for each channel versus operational temperature is presented. The calculus is performed based on sensitivity equations and the estimated values for different uncertainties source

In this work, a new technique for the computation of the region of attraction for linear and time invariant systems controlled by a saturated reset control system is presented. The estimation of the region of attraction is based on a polytopic representation. In addition, the information of the solutions is synthesized in a directed graph formed by the polytopes. After presenting several useful conditions on the polytopes, such as positive invariance and convergence to the origin, a procedure is proposed to process the graph and obtain a region of attraction estimation. The effectiveness of the proposed technique is illustrated by a numerical example.

This work approaches the problem of robust control for distributed collector fields. The goal is to investigate the potentials of a nonlinear/hybrid compensator previously developed by some of the authors, referred to as the PI+CI compensator, in the control of a system with significant uncertainty. To this end, the design of PI+CI has been made in two steps: first, a base robust PI compensator is designed by using QFT (quantitative feedback theory) to satisfy (robust) relative stability and tracking specifications, and then a reset percentage of the integral term is chosen in order to improve the transitory response. In addition, a simple modification of the PI+CI compensator, consisting of the variation of the reset percentage at each reset time, is investigated regarding the improvement of the previous design.

A general framework for designing antiwindup control systems is developed. More traditional anti-windup schemes generally suffer from several limitations, including the lack of (a priori) robustness respect to plant uncertainty, and also have a considerable heuristic component. The design method proposed in this paper provides an accurate graphic design procedure that guarantees closed loop global stability, in the presence of saturation-type non-linearities and plant uncertainty. The case of SISO LTI plant is considered.