Actuator Fault Estimation (FE) and Fault Tolerant Control (FTC) strategies designed with model-based observers for Vertical TakeOff and Landing (VTOL) aerial vehicles are proposed and validated experimentally in this paper. Three observers are considered for FE: a nonlinear adaptive observer and a linear Proportional-Integral Observer (PIO) applied to a Planar VTOL and a quasi-Linear Parameter Varying (qLPV) PIO applied to a quadcopter vehicle. The fault detection is done by comparing the fault estimation signal with a predefined threshold. Fault isolation is achieved by analyzing the sign of the fault estimation signal. The Available Control Authority Index (ACAI) method is used to analyze the controllability properties of the vehicles under actuator faults. The main contribution of this work is the design and the experimental validation of complete active FTC schemes by using the proposed FE systems in order to accommodate a soft actuator fault and reconfigure an aggressive fault, even when the vehicle is flying in a non-hover position. Finally, the proposed FTC schemes are validated in different cases of flight tests for illustrating the effectiveness of the strategies.

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Given the imminent threats of climate change, it is urgent to boost the use of clean energy, being wind energy a potential candidate. Nowadays, deployment of wind turbines has become extremely important and long-term estimation of the produced power entails a challenge to achieve good prediction accuracy for site assessment, economic feasibility analysis, farm dispatch, and system operation. We present a method for long-term wind power forecasting using wind turbine properties, statistics, and genetic programming. First, due to the high degree of intermittency of wind speed, we characterize it with Weibull probability distributions and consider wind speed data of time intervals corresponding to prediction horizons of 30, 25, 20, 15 and 10 days ahead. Second, we perform the prediction of a wind speed distribution with genetic programming using the parameters of the Weibull distribution and other relevant meteorological variables. Third, the estimation of wind power is obtained by integrating the forecasted wind velocity distribution into the wind turbine power curve. To demonstrate the feasibility of the proposed method, we present a case study for a location in Mexico with low wind speeds. Estimation results are promising when compared against real data, as shown by MAE and MAPE forecasting metrics.

The rise for innovation in the electrical industry is strongly driven by development of new materials. Features of new materials are changing design paradigms for engineers. In this paper, the electrical properties of films of cellulose nanocrystals were measured. It was found that humidity affects the dielectric strength on the cellulose nanocrystals (CNCs). The dielectric strength was similar to the value of the industrial dielectric paper. The addition of plasticizer improved the flexibility of the material but lowered the dielectric strength. The films of CNC had an ordered arrangement, as suggested by the iridescence shown by them. The humidity content of the films was measured by thermogravimetric analysis. The CNC film was used for assembling a capacitor and compared to a capacitor assembled with dielectric paper.