Complex thermo-kinetic interactions during metal additive manufacturing reduce the homogeneity of the microstructure of the produced samples. Understanding the effect of processing parameters over the resulting mechanical properties is essential for adopting and popularizing this technology. The present work is focused on the effect of laser power, scanning speed, and hatch spacing on the relative density, microhardness, and microstructure of 316L stainless steel processed by laser powder bed fusion. Several characterization techniques were used to study the microstructure and mechanical properties: optical, electron microscopies, and spectrometry. A full-factorial design of experiments was employed for relative density and microhardness evaluation. The results derived from the experimental work were subjected to statistical analysis, including the use of analysis of variance (ANOVA) to determine both the main effects and the interaction between the processing parameters, as well as to observe the contribution of each factor on the mechanical properties. The results show that the scanning speed is the most statistically significant parameter influencing densification and microhardness. Ensuring the amount of volumetric energy density (125 J/mm³) used to melt the powder bed is paramount; maximum densification (99.7%) is achieved with high laser power and low scanning speed, while hatch spacing is not statistically significant.

The development of biofuels aligned with the circular economy has gained increasing attention as a sustainable alternative to non-renewable energy sources. This study aims to evaluate the physical and thermal properties of biomass briquettes derived from potato stalk residues to assess their potential as biofuels. For this, dried potato stalk residues were subjected to pyrolysis for carbonization, followed by grinding and mixing with potato and achira binders in proportions of 10% and 20%, respectively. The briquetting process was performed at a pressure of 10 MPa with compaction times of 30 and 60 s. Scanning electron microscopy (SEM) revealed a porous structure with uniform binder distribution, while Raman spectroscopy confirmed the presence of D and G bands, indicative of amorphous carbon structures with graphite-like imperfections. Thermogravimetric analysis (TGA) determined a moisture content of 10%, which ensures stability. Non-carbonized briquettes exhibited higher compressive strength, withstanding forces in excess of 400 N at 20% deformation. The average calorific value of both briquette types was 15 MJ/kg, comparable to biofuels derived from sugarcane bagasse and rice hulls, with samples exceeding the 12 MJ/kg threshold for biomass fuel classification. These results indicate that potato stalk briquettes could be a viable biofuel alternative to support renewable energy diversification.

El objetivo de este proyecto fue establecer propuestas de prevención y control de riesgos psicosociales que provocan estrés en los conductores de camionetas de alquiler de la compañía El Mirador Yaruqueño. Los peligros psicosociales que provocan estrés en los conductores según el cuestionario OIT-OMS son: tecnología (100 %) y clima organizacional (89 %). El método FPSICO identificó: carga de trabajo (41 %), participación - supervisión (41 %), desempeño del rol (47 %) y tiempo de trabajo (41 %). La evaluación de los riesgos psicosociales que causan estrés en el trabajo según el cuestionario OIT-OMS, el 76 % tienen un “bajo nivel de estrés”. El método FPSICO 4.0 evaluó los riesgos psicosociales en estado crítico: “inseguridad laboral” con el factor interés por trabajo/compensación (58,8 %) y “trabajo emocional” con el factor demandas psicológicas (35,3 %). En estado medianamente crítico se encuentra el riesgo “violencia laboral” con el factor relaciones y apoyo social (41,2 %). Para reducir el nivel de riesgo se ejecutaron en un período de 60 días las siguientes acciones: capacitación del manejo de aplicaciones móviles para comunicación y geolocalización, capacitación respecto servicio al cliente, ejecución de pausas activas, concientización de los efectos del alcoholismo, programación de turnos de trabajo. Los índices de seguimiento de la compañía, evaluaron la eficacia de medidas propuestas en tres escenarios, antes, durante y después de la implementación, en períodos bimensuales entre 15 de septiembre del 2021 al 15 de febrero del 2022. Al comparar el primero y segundo escenario, se obtuvo una disminución bimensual del 25 % en reclamos por mal servicio, 33 % en infracciones de tránsito y 0,88 % en ausentismo del personal, mientras que el índice incidente se duplicó, respecto a los meses anteriores. La comparación del segundo y tercer escenario, muestran la reducción del, 50 % en incidentes de tránsito y 5,9 % en ausentismo del personal, mientras que reclamos por mal servicio e infracciones de tránsito se mantuvieron en el mismo valor bimensual. En el programa de intervención psicosocial las acciones propuestas, para el corto plazo, se implementaron en su totalidad, 66,6 % de mediano plazo y 15,3 % de largo plazo.

This study presents the design and implementation of a collaborative robot (cobot) intended as an educational tool for robotics within the STEM framework. The cobot integrates direct and inverse kinematics for motion control and joint-level mechanical impedance modulation. It also features a user-friendly interface with a digital twin. The prototype was fabricated using additive manufacturing and optimized via CAD/CAE tools. It achieved a positioning accuracy of ±6.19 mm, which was validated under ISO 9283 standards. The digital twin serves not only as a technical support tool but also as a teaching resource, providing immediate visualization of robot states and motion. This helps learners connect kinematic and control concepts with observable behavior. The system supports autonomous ”Learning” and ”Reproduce” functions, bridging the gap between theoretical concepts and practical applications. These modes enable repeatable experimentation, allowing students to record and reproduce trajectories and to contrast the physical execution with its synchronized virtual representation. This reinforces understanding through guided trial and improvement. The Cobot involves learners in fundamental STEM disciplines, including computer programming, engineering design principles, mathematical concepts, and systems-oriented thinking. The collaborative robot has significant potential as an effective pedagogical platform that promotes interdisciplinary education and practical problem-solving in robotics. Finally, statistical analysis confirmed the normality of the data and the reliability of the performance data, further supporting its value in learning environments.