Universidad Tecnológica de Bolívar
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Automatic differential kinematics of serial manipulator robots through dual numbers
No full textDual Numbers are an extension of real numbers known for its capability of performing exact automatic differentiation of one-valued functions theoretically without error approximation. Also, Differential Kinematics of robots involves the computation of the Jacobian, which is a matrix of partial derivatives of the Forward Kinematic equations with respect to the robot’s joints. Thus, to perform the automatic calculation of the Jacobian matrix, this paper presents an extension of dual numbers composed of a scalar real part and a vector dual part, where the real part represents the angular value of the robot joint, and the dual part represents the direction of the corresponding partial derivative for each joint. The presented method was implemented in Matlab through Object Orientes Programming (OOP), and the results for calculating the Jacobian of the KUKA KR 500 robot model for 1000 random postures were subsequently compared in terms of execution time and Mean Squared Error (MSE) with other conventional methods: the geometric method, the symbolic method, and the finite difference method. The results showed a significant improvement in the computing time for calculating the Jacobian of the robotic model compared to the other methods, as well as a minimum MSE having as reference the numerical value of the symbolic calculations
Simulation environment development and control for path tracking in greenhouse harvesting and crop transportation with mobile robots
No full textThis research presents a trajectory tracking methodology designed for differential drive mobile robots (DDMR), specifically focused on agricultural robotics applica- tions. The study encompasses a detailed exploration of the kinematic model of these robots, both for unicycle models and robots with Mecanum wheels, as well as a dy- namic analysis of them. Additionally, the design and validation of control techniques such as Proportional-Integral-Derivative (PID) control for Direct Current (DC) mo- tors, Model Predictive Control (MPC) with nonlinear feedback based on Lyapunov, and linear feedback control are carried out. The validation and integration between the designed control systems and the kinematic models are performed in two de- signed simulated environments, using the Robot Operating System (ROS) and a Python-based environment. This approach allows for perfect coordination of the system, incorporating trajectory generation using ArUco markers along with vari- ous trajectory planning strategies such as A* (A Star), Rapidly-exploring Random Trees (RRT), and Dynamic Window Approach (DWA), in order to generate work routes within the agricultural work environment, in our case study, the methodology is applied within a greenhouse setting. This strategy considers various operational phases, including initiation, harvesting, and the transportation of produce to the designated storage area. Python environment works as a preliminary interface to validate and adjust the parameters of the controllers and algorithms for optimization and trajectory gen- eration, while Gazebo and ROS integrate seamlessly to create a cohesive system architecture that allows validating the behavior of the designed model under real conditions. The results show the practical feasibility of the proposed methodology, demonstrating good accuracy in trajectory tracking both in the simulations within the greenhouse environment and in the validation in the Gazebo environment. The maximum average Mean Squared Error (MSE) was 1.68 × 10−4, and the average Integral of Absolute Error (IAE) was 4.25×10−3 for the trajectories within the sim- ulated environment in Python for the greenhouse. Meanwhile, for the environment in Gazebo, the maximum average Mean Squared Error (MSE) was 1.68 × 10−4, and the average Integral of Absolute Error (IAE) was 4.25 × 10−3. A notable aspect of this approach is its implementation in a specially developed virtual environment. The simulation in a controlled environment not only offers a platform for testing and refining algorithms in a safe context but also provides the opportunity to anticipate and resolve potential challenges before their application in real-world settings.Universidad Tecnológica de BolivarMagíster en IngenieríaMaestrí
Multi-objective grounding system optimisation using NSGA-II
No full textThis study investigates the optimisation of grounding infrastructure in substations by implementing the philosophy of the multi-objective algorithm NSGA-II Elite. A complete description of the operating scheme and the characteristic mechanisms that support the behaviour and development of optimal Pareto solutions is provided. A detailed comparison was made with the optimisation method used in the GMAT program of Aplicaciones Tecnológicas, based on a semi-optimization process derived from the correlation of semi-precision optimisation solutions. The results show that multi-objective optimisation using NSGA-II results in a significant cost reduction compared to the semi-optimization method, although the computational time required to reach the final solution increases significantly. This approach allows a more adequate understanding of optimising the terrestrial substation grid. It highlights its ability to generate more cost-effective and performance-efficient solutions by carefully considering the computing time required
Gestión Educativa de las Prácticas pedagógicas pro-paz en el marco del posacuerdo. Caso Corporación Universitaria Reformada (Barranquilla, Colombia)
No full textEl presente trabajo busca realizar una sistematización de las prácticas pedagógicas por la paz que la Corporación Universitaria Reformada ( CUR) viene realizando al interior de las aulas, así como los diferentes espacios en los cuales participa de manera activa en pro de la paz y en el marco de los post acuerdos con el fin de identificar temáticas o aspectos relevantes para nuestro actual contexto, desde los actores educativos participes de la misión y visión institucional buscando paralelamente identificar aspectos a mejorar para fortalecer las mismas. El objeto de sistematizar e identificar estas experiencias al interior de la CUR es de vital importancia para fortalecer y cualificar el trabajo que se viene realizando desde los actores educativos y la participación de éstos en espacios y organizaciones que se encuentran trabajando con las víctimas del conflicto armado. En esta investigación, se realizó un acercamiento a las diferentes prácticas pedagógicas por la paz que se llevan a cabo al interior de la CUR, una descripción del contexto que afecta desde esas acciones, prácticas y acompañamiento, así como de la comprensión que los actores educativos tienen y perciben sobre las mismas y sus alcances no solo a nivel institucional, sino local y regional. También un análisis sobre los aspectos que se pueden mejorar y que potencializarían las prácticas que actualmente se están implementando al interior de la institución. Para llevar a cabo dicha investigación hemos seguido la metodología cualitativa haciendo uso de los siguientes instrumentos: Técnica de entrevista estandarizada y análisis de resultados. En esta investigación se concluye, que es necesario seguir trabajando en proyectar una propuesta de formación en acciones pro paz, con las temáticas ya identificadas, tales como: reparación, bienestar, restitución, justicia, verdad, cuidado del medio ambiente y equidad de género, para fortalecer los conocimientos y las practicas pedagógicas por la paz que actualmente se vienen implementando, con el objeto de cualificar sus conocimientos para realizar un trabajo pertinente en la atención e intervención de las víctimas del conflicto armado en tiempos de postconflicto presentes al interior y fuera de la CUR
Diseño de una herramienta de registro y digitalización de defectos presentes en el área de ajuste de la empresa Auteco S.A.S
No full textWithin the operational headquarters, a great diversity of processes are carried out in different work areas, for this project the operation of the adjustment area of the company was taken as a reference. This area is mainly in charge of evaluating and correcting those parts that present any defect or nonconformity. One of the activities carried out in this area is that the registration of this information is done manually, and its respective evidence is shown through a WhatsApp line or chat. All the information recorded is stored in digital media in temporalities after the day of registration. There is an opportunity for improvement in this regard, which stems from the difficulty in making decisions due to an inefficient flow of information that limits the ability to respond in real time to the defects that have been occurring. This is why the requirement provided by the company refers to improve the process of recording defects in the adjustment area and that the tool used for this improvement is adapted to the applications with which operators are familiar. On the other hand, the proposed solution to address this issue consists of the creation of three products, which are considered the main stages of the design, each with various associated activities and tasks. The three products are summarized below: • Microsoft Forms: A form was implemented using Microsoft Forms to facilitate the efficient digitization of information. This form allows for the collection of both manually entered data and photographs of defects sent via WhatsApp. • Excel: Using Power Automate, an information flow was established that allows the collected information to be sent directly to the storage system, in this case Excel. This ensures that the data is recorded in real time in the Excel file. • Power BI: Finally, a dashboard or report was created using the Power BI tool. In addition to showing some related indicators, this report presents a heat map graph highlighting the areas of the motorcycle with the most defects. All of this required both the application of knowledge acquired in subjects such as: Operations Strategy, Productivity Engineering, Data Science, Ergonomics, as well as the knowledge achieved in the realization of the project such as: data management, Power Automate, Power BIUniversidad Tecnológica de BolívarIngeniero IndustrialPregrad
Club de Lectura Libro playa un mar de saberes: apuestas para su consolidación y sostenibilidad
No full textLa presente investigación da cuenta de las condiciones bajo las cuales se realizan las actividades del club de lectura Libro playa: un mar de saberes, su organización y gestión; emprendimiento cultural ubicado en el municipio de Santiago de Tolú, Sucre. Este proyecto de asesoría identifica los aspectos o áreas donde se encuentran sus principales fortalezas y dificultades con el propósito de dar cuenta de qué capacidades son relevantes para dicho emprendimiento cultural, cuáles requiere fortalecer y cuáles se deben generar. Se responde a esta cuestión usando como marco principal el desarrollo humano, el enfoque de capacidades a partir de Sen, los postulados acerca de la lectura como capacidad cultural, y un abordaje en términos metodológicos desde el enfoque cultural de desarrollo y la metodología de emprendimientos culturales. Durante el proyecto de asesoría, se contó con la participación de los actores principales del club de lectura, el contexto local y la realidad departamental en términos de políticas culturales alrededor de la lectura, la escritura y la oralidad. Finalmente, se proponen un conjunto de lineamentos estratégicos en el marco de las capacidades de gestión, acción y formación, tanto de las instaladas como requeridas, orientando el ejercicio a fortalecer su consolidación y sostenibilidad como iniciativa comunitaria.Universidad Tecnológica de BolívarMagister en Desarrollo y CulturaMaestrí
Real-time hardware-in-loop system based validation of vehicle-grid interface for bidirectional power flow control
No full textIn the context of modern sustainable transportation technology, the terms Vehicle-to-Grid (V2G) and Grid-to-Vehicle (G2V) holds significant value. During V2G and G2V modes, vehicle and grid exchange power using various power converters to modulate the power for a sustainable electrical energy ecosystem. With V2G, the EVs can also perform the role of a peak power contributor, reserve power source, and an efficient system to improve power quality issues by working as power factor corrector, reactive power compensator, and active power filter, to name a few during the V2G mode. The on-board power converter in the vehicle, working as the charger for the battery, is the component required to facilitate the intended bidirectional power exchange between the vehicle and grid and also modulates the power as and when required. The modality for operating the onboard charger as a power exchange tool depends on the type of control strategy adopted as well as on the battery and grid parameters. In this paper, a bidirectional power converter (on-board converter) is introduced, which is controlled by adopting a d-q axis-based control strategy. The MATLAB/SIMULINK-based system simulation model is created, and the Hardware-in-Loop (HIL) tool Opal-RT 4510 is used to validate the simulation results on the intended hardware and real-time scenario. The control strategy, when integrated with the adopted model, contributes to enhancing the power-transferring capability of the converter, which is assessed using the simulation and subsequent HIL-based implementation. The paper also focuses on narrating the steps to implement the vehicle-grid interface using HIL and forming a generic reference model for a bidirectional power flow converter, such that it can be used for other circuits and its implementation in real-time scenarios
Anatomy of the economic value generated by a cultural event
No full textEl artículo mide los efectos económicos de las decisiones tomadas por dos agentes del sector cultural y creativo. Los gestores de un evento cultural deciden producirlo: movilizan un flujo de artistas y creativos que materializan sus creaciones. Los individuos deciden visitarlo: movilizan un flujo de individuos que producen experiencias al asistir al evento. El resultado se revela en la dimensión económica del valor generado por un evento cultural: nuevos ingresos y empleos para el territorio anfitrión del evento y experiencias culturales únicas y auténticas para los asistentes al evento. La literatura empírica ha llamado la atención sobre la necesidad de medidas más precisas del valor económico, en particular que no sobrestimen. Se utiliza una combinación de instrumentos: entrevistas (n = 6) a gestores/organizadores de eventos; una encuesta presencial (n = 173) a representantes de puestos comerciales; una encuesta presencial a asistentes (n = 1.030); y, se adapta un modelo de entrada-salida al área de impacto. El artículo proporciona un marco metodológicamente útil para identificar y estimar medidas más confiables del valor material (económico) creado por un evento cultural, que puede replicarse en una variedad de eventos alrededor del mundo.The article measures the economic effects of decisions made by two
agents in the cultural and creative sector. Managers of a cultural event decide
to produce it: it mobilizes a flow of artists and creatives who materialize their
creations. Individuals decide to visit it: it mobilizes a flow of individuals who
produce experiences by attending the event. The result is revealed by the economic dimension of the value generated by a cultural event: new income and
jobs for the host territory of the event and unique and authentic cultural experiences for those attending the event. The empirical literature has drawn attention
to the need for more precise measures of economic value, in particular that
do not overestimate. A combination of instruments is used: interviews (n = 6)
with event managers/organizers; a face-to-face survey (n = 173) with representatives of commercial stalls; a face-to-face survey of attendees (n = 1,030); and,
an input–output model is adapted to the area of impact. The article provides a
methodologically useful framework for identifying and estimating more reliable
measures of the material (economic) value created by a cultural event, which can
be replicated in a variety of events around the worl
Propuesta pedagógica para el fortalecimiento de la lectura y escritura en estudiantes de básica primaria de la institución educativa 14 de Febrero, en Cartagena
No full textEl objetivo principal de esta investigación fue desarrollar una propuesta pedagógica destinada a fortalecer las habilidades de lectura y escritura en estudiantes de tercer, cuarto y quinto grado de la Institución Educativa 14 de febrero en Cartagena. Para lograr este propósito, se realizó un exhaustivo diagnóstico de las dificultades que enfrentan los estudiantes en estas áreas dentro del contexto escolar. El enfoque metodológico empleado fue mixto, permitiendo así obtener una comprensión detallada de las dificultades específicas en lectura y escritura que afectan a los estudiantes. Esta investigación contó con la participación del 100% de los estudiantes de educación básica primaria matriculados en los grados 3°, 4° y 5° de la Institución Educativa. Además, como parte integral del proceso de diagnóstico, se incluyeron 10 docentes de diversas áreas de conocimiento que imparten clases en estos grados. Dado el carácter instrumental de la lectura y la escritura en el proceso educativo, los docentes se convirtieron en informantes clave sobre el desarrollo de los estudiantes en estas competencias, aportando una perspectiva valiosa desde su experiencia en el aula. De igual manera, aportaron elementos valiosos para la construcción de la propuesta que se presenta en este trabajo
Tracking tumors via convolutional neural networks in ultrasound images
No full textIn certain medical applications, ranging from real-time surgical monitoring to noninvasive diagnosis, it is vital to accurately identify and localize tumors in ultrasound images. Despite advances in deep learning (DL), there are still challenges in adapting these models for specific tasks in fields where data unavailability and the complexity of medical imaging are common. This study presents a self-monitoring approach for tumor tracking using ultrasound images. Additionally, the MATLAB Ultrasound Toolbox (MUST) was used to simulate various properties of the ultrasound images and to employ Optuna for hyperparameter optimization. Also, add the RUS-6000A portable ultrasound machine and the ATS-539 phantom allows the performance of the model to be evaluated in more realistic conditions. This methodology aims to improve the accuracy of tumor detection using limited data. The experimental results suggest that the model maintains relatively constant performance under different image contrast conditions, demonstrating its adaptability and reliability. However, it also suggests that additional tests should be performed to validate its generalization in real-world cases.Magister en Ingeniería59 páginas. Tablas y figura