Abstract
The materials used in the transport industry have been changing in the last decades. The traditional and heavy steel have been switching by the light alloys like aluminum alloys. However, despite their advantages as low density and high corrosion resistance, the manufacturing process, especially fusion welding, is very demanding and challenging. In the transport industry, most of the hyperstatic components made in aluminum alloys are welded manually with the associate financial costs as well as the lack of quality and repeatability. For these reasons, it is urgent to develop new methodologies to automate this process. The present work intends to show a scientific method to automate the welding process of hyperstatic frames, very common in bicycles, made in aluminum alloy. This methodology involves two steps, the first one in which is performed numerical simulations to determine the optimal welding parameters to minimize the distortion and residual stresses. The second step is experimental one, and it is created an automated welding cell with a robot to weld the frames. It has been proved that it is possible to obtain welding aluminum frames with acceptable quality in agreement with the ASME IX standard. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2021.

Abstract
Distributed power sources will become increasingly ubiquitous in the near future. In this power production paradigm, photovoltaic conversion systems will play a fundamental role due to the growing tendency of energy price, and an opposed trend for the photovoltaic panels. This will lead to increased pressure for the installation of this particular renewable energy source in home buildings. In particular, on-grid photovoltaic systems where the generated power can be injected directly to the main power grid. This strategy requires the use of DC-AC inverters whose output is synchronized, in phase, with the main grid voltage. In order to provide steady output in the presence of load disturbances, the inverter must work in closed-loop. This work presents a new way to design an inverter controller by resorting to the CDM design technique. The obtained results suggest that the controller achieved with this method, although simpler than other methods, leads to an acceptable and robust closed-loop response. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2021.

Abstract

Abstract
One of the most important negative consequence in the fusion welding processes is the generation of tensile residual stresses in welded joints. The main goals of this work are to determine the optimal combination of welding parameters to minimize the residual stress level and the influence of each welding parameter in that feature to weld 6082-T6 aluminum alloy plates using the GMAW welding process. To achieve these goals was implemented the Taguchi orthogonal array (L27) to define the design of numerical and experimental tests. All combinations were simulated in the Simufactwelding 6.0 software, from which it was possible to obtain the values of maximum residual stresses. The data treatment was carried out, reaching the combination of levels for each parameter. With ANOVA analysis was found that the parameter with the greatest influence in the residual stress generation was the welding speed, while the parameter with the least influence was the torch angle. Also, to minimize the residual stresses it was observed that the optimal combination of welding parameters is welding current intensity of 202 A, welding speed of 10 mm/s, and 30 degrees of inclination of the angular torch. The two simulations that resulted in the highest and lowest residual stresses were validated experimentally by the hole drilling method to measure the residual stresses.

Abstract
In recent years and after the strong impact of the last global health emergency (COVID-19) information and communication technologies have had a great impact on society but particular in the teaching-learning process. Education has been impacted at all its levels. Therefore, education models have been to be adapted to this new challenging paradigm by using different tools such as videoconferences, simulations, on-line interactive applications, virtual and remote laboratories, robots, etc.The objective of this work is to elaborate a systematic mapping to know what scientific from its beginning to 2020, identifying the most literature exists regarding simulators, remote and virtual laboratories focused on STEM/STEAM skills development in the educational context. To do so, bibliographical data gathered of four of the most popular and complete electronic databases (ACM, IEEE, Scopus and Web of Science). At the begging we selected 1232 articles after applying the acceptance criteria defined as part of the search and select strategy, we had 61 articles that help us to answer some questions like what are the most popular virtual and remote labs? or what are the current trends and issues of these tools? and the future ones? © 2021 IEEE.

Abstract
Digital society demands very qualified professionals ready to this environment challenges. This makes necessary to foster the development of competences related to such context such as Computational Thinking or STEAM related skills. However, this is not an easy task, especially because integrating subjects that covers the necessary topics and competences. New active pedagogical approaches are required and this what RoboSTEAM project provides. The application of Challenge Based Learning and Physical Devices and Robotics facilitate the so named twenty first century skills. The project has been developed by several universities and schools and one of most critical parts was testing the methodology and tools, this was done into pilot phases that are described in the present work. The results show that there are important differences between partners socioe-conomical context, but that the outcomes of the project are flexible enough to be applied successfully in any of them.