In this paper, we analyze the limitations that impose the presence of uncertainty in the design of optimal energy management strategies (EMSs) for fuel cell (FC) hybrid electric vehicles. Using an electric powertrain constituted by a hydrogen FC and a battery bank, the fuel consumption minimization problem is analyzed in the presence of parametric uncertainty. The conditions that ensure that the nominal optimization problem matches the solution of the real (unknown) optimization problem are clearly stated. By observing that the uncertainty will limit the feasible solutions of the minimization consumption problem, supervisory control constituted by heuristic rules is proposed to face such limitations, resulting in a mixed optimal-heuristic EMS. The effect of the powertrain design, driving cycle, and initial conditions in the proposed strategy is discussed. Numerical simulations provide evidence of the advantages and features of the supervisory control strategy.

Worldwide, the shortage of fresh water has increased exponentially due to population growth and contamination of available water, especially in water tables that provide water for general consumption. One of the main pollutants of water is arsenic (As), present in the environment and in most mining/metallurgical processes, which is a major health risk, especially as a carcinogen. In the region of Matehuala, San Luis Potosi (SLP), Mexico, a highly productive mining area, arsenic concentrations of 138.1 mg/kg have been found in soils—6.2 times higher than what is allowed in domestic soils, while in water it is reported up to 158 mg/L, exceeding permissible limits for human consumption. In addition to As pollution, the region suffers from water shortage both in the city and in rural communities. Therefore, it is necessary to explore new technologies to provide the population with fresh water. This paper presents a feasibility study on the use of an atmospheric water generator (AWG) to capture fresh water in the region of Matehuala, SLP. The region was found to have the necessary environmental conditions to use AWGs, with an annual average relative humidity (RH) of approximately 60%. Using a mathematical model of a dehumidifier, water harvesting can be evaluated under the region’s prevailing climatic conditions. The month with lowest harvest was found to be January, with 0.89 to 3.6 L/day, while the month with largest harvest was August at 3.9 to 18 L/day and water production costs of 0.0093 and $ 0.038 USD/L, respectively. The study concludes that the use of AWGs would help alleviate water shortages, thus benefiting marginalized people or communities, preserving ecosystems and the environment.

The rheological characterization of fluids using a rheometer is an essential task in food processing, materials, healthcare or even industrial engineering; in some cases, the high cost of a rheometer and the issues related to the possibility of developing both electrorheological and magnetorheological tests in the same instrument have to be overcome. With that in mind, this study designed and constructed a low-cost rotational rheometer with the capacity to adapt to electro- and magneto-rheological tests. The design team used the method of continuous improvement through Quality Function Deployment (QFD) and risk analysis tools such as Failure Mode and Effect Analysis (FMEA) and Finite Element Analysis (FEA). These analyses were prepared in order to meet the customer’s needs and engineering requirements. In addition to the above, a manufacturing control based on process sheets was used, leading to the construction of a functional rheometer with a cost of USD $1500.

The use of electric vehicles and their various configurations is seen as a major alternative in efforts towards reducing pollutant emissions from motor vehicles that continue to use fossil fuels. Electric transport technology presents more efficient means of energy conversion in vehicles: electric (EV), hybrid (VH), and hybrid electric (HEV) vehicles. For example, the energy storage system in the latter can be made up of ultracapacitors (UCs), batteries (Bs), and fuel cells. This work focuses on HEVs powered by batteries and ultracapacitors. In particular, the multiple converter configuration (C-CM) for the HEV powertrain system is analyzed using electric models of the vehicle powertrain components. To analyze the multiple converter configuration, parameters of a vehicle taken from the literature and the electrical model of the configuration were developed. With the above, the proposed configuration was evaluated before driving cycles (CITY II and ECE) and the configuration performance was compared with respect to other configurations. In the C-CM model, limitations in the choice of the number of Bs and UCs were observed in the powertrain depending on the maximum power of both energy sources and vehicle load demand. The results show that more energy is extracted from the batteries in the ECE cycle than in the CITY taking into account that the batteries are used as the main power source. C-CM results compared to other configurations show that energy extracted from batteries in the CITY is the same across all configurations. While energy consumption is lower in the ECE, C-CM results were not very significant compared to other configurations. However, the C-MC has the advantage of having better power flow control due to having two converters, thus improving HEV safety.

Gyroscopic systems and their properties have been extensively studied as Angular Momentum Devices (AMD), Control Moment Gyros (CMG) or Gyroscopes for various applications such as structure control, stability or energy storage. However, most of the works that have been done are theoretical and do not present experimental implementation. In this work we performed an experimental study of a gyroscope beam system (gyroelastic beam) focused systems on the deflection of cantilever beams or the control of flexural stresses. We first used a simple two-degree of freedom model to better understand the terms governing the design, construction and experimental evaluation of gyroelastic beam systems. We then performed experimental tests at different velocities of the gyroscopic actuator and measured the deflection of the system. The results showed that it is possible to have control of the deflection and the bending forces for this type of configurations which can be exported to helicopter blades or wind turbine blades.