Soft computing techniques applied to modelling and control of unmanned aerial vehicles

Tesis inédita de la Universidad Complutense de Madrid, Facultad de Informática, leída el 18-06-2019El uso de UAVs (vehículos autónomos aéreos), y en concreto, de cuatrirrotores o drones, está creciendo de día en día, y se espera que se usen en multitud de aplicaciones: rescate, seguridad,lucha contra incendios, agricultura, inspección de estructuras, logística, … En la mayoría de estas tareas los cuatrirrotores deben actuar de una forma totalmente autónoma. Estas aplicaciones y las que están por llegar requieren el diseño de modelos y controladores eficientes y robustos para esos vehículos no pilotados. Sin embargo, esta no es una tarea sencilla debido, entre otras causas, a la aleatoriedad de los flujos de aire, la dinámica altamente no lineal del UAV, el acoplamiento entre sus variables internas, etc. Estos factores hacen que las técnicas de Soft Somputing (computación suave, una rama de la Inteligencia Artificial), y entre ellas concretamente las redes neuronales artificiales y la lógica fuzzy, sean un enfoque prometedor para la identificación y el control de estos sistemas...The use of UAVs (unmanned aerial vehicles), and specially quadrotors, is growing day by day, they are planned to be used in multitude of valuable applications: rescue, security, firefighting, agriculture, structure inspection, logistics, … In most of those tasks, the quadrotorsare expected to be fully autonomous. All these applications and those to come, demand the design of efficient and robust models and controllers for those autonomous vehicles. However, this is not an easy task due to, among others: the randomness of the airstreams, the high nonlinearity dynamics, the coupling between the internal variables, etc. These factors make the Soft Computing techniques (a field of the Artificial Intelligence), and among them specially the artificial neural networks and the fuzzy logic, a promising approach for the identification and control of these systems...Fac. de InformáticaTRUEunpu

Frequencies identification of NREL 5MW ITI Barge Wind Turbine: first approach

In this work we present a process to identify the main frequencies that affects a floating offshores wind turbine (FOWT), specifically, the NREL 5MW ITI Barge Wind Turbine. This floating platform is highly affected by surge and sway translational movements due to the strong winds and mainly the waver it is subjected to. However, one of the most important modes is the 1st tower fore-aft bending mode, whose frequency has the same value than the forced 3P component, provoking these frequencies to be highly excited. In this work this effect is observed in the power spectrum of the tower top acceleration signal along the nacelle “x” axis.Peer Reviewe

Control de un vehículo cuatrirrotor basado en redes neuronales

[Resumen] En este trabajo se propone una estrategia de control neuronal adaptativa para estabilizar un vehículo aéreo no tripulado (UAV). Se estudia la influencia de la masa del cuatrirrotor y de las perturbaciones. Los resultados muestran cómo el aprendizaje online hace más robusto el control, minimizando los efectos de las variaciones en la masa y de las perturbaciones externas en la altura

Modelling of a hybrid differential-tricycle AGV

[EN] In the industrial field, Automatic Guided Vehicles (AGV) are frequently used for the transport of goods, usually replacing manual means of transport or conveyor belts, to reduce operating costs and human errors in this way. In order to increase the performance of these industrial systems and enable more advanced applications, it is key to develop control-oriented models to test new strategies and control techniques, with the aim of making them safer and more efficient. Thus, in this work a kinematic and dynamic control-oriented model of an AGV is developed. The main objective of this work is to obtain a mathematical representation of the complex dynamics of the AGV Easybot, a hybrid tricycle-differential vehicle, which will allow us to study the effects of towed load and wheel-ground interaction. To do so, the kinematic models of the differential and the tricycle robot have been developed and combined together with the developed vehicle dynamics model. The AGV has been split into its different components and the Newton-Euler equations have been applied to obtain the equations of its dynamics. The model has been validated in simulation for different trajectories, varying the speed and the load.[ES] En el ámbito industrial se utilizan con frecuencia Vehículos de Guiado Automático (AGV) para el transporte de mercancía puntual, normalmente sustituyendo a los medios de transporte manuales o a las cintas transportadoras, para así reducir costes operativos y errores humanos. Para aumentar el rendimiento de estos sistemas industriales y que puedan realizar funcionalidades más avanzadas, es fundamental desarrollar modelos orientados al control que permitan probar nuevas estrategias y técnicas de control que los hagan más eficientes y seguros. Para ello, en este trabajo se desarrolla un modelo cinemático y dinámico orientado al control de un AGV. El principal objetivo del trabajo es conseguir una representación matemática de la compleja dinámica del AGV Easybot, un vehículo híbrido triciclo-diferencial, que permita estudiar los efectos de carga remolcada y la interacción rueda-suelo. Para ello se ha desarrollado el modelo cinemático de la parte diferencial y del triciclo, y se han combinado ambos entre sí y con el desarrollo de la dinámica del vehículo. Se ha descompuesto el AGV en sus distintos módulos y se han aplicado las ecuaciones de Newton-Euler para obtener las ecuaciones de su comportamiento dinámico. El modelo se ha validado en simulación para diferentes trayectorias, variando la carga y la velocidad.Sánchez, R.; Sierra-García, JE.; Santos, M. (2021). Modelado de un AGV híbrido triciclo-diferencial. Revista Iberoamericana de Automática e Informática industrial. 19(1):84-95. https://doi.org/10.4995/riai.2021.14622OJS8495191Abderrahim, M., Bekrar, A., Trentesaux, D., Aissani, N., & Bouamrane, K. (2020). Manufacturing 4.0 Operations Scheduling with AGV Battery Management Constraints. Energies, 13(18), 4948. https://doi.org/10.3390/en13184948ASTI MOBILE ROBOTICS, S. (2021). ASTI - Mobile Robotics. Astimobilerobotics.com. Retrieved 12 February 2021, from https://www.astimobilerobotics.com/.Bi, Z. M., Lang, S. Y., & Wang, L. (2008). Improved control and simulation models of a tricycle collaborative robot. Journal of Intelligent Manufacturing, 19(6), 715-722. https://doi.org/10.1007/s10845-008-0122-4Belman-López, C. E., Jiménez-García, J. A., & Hernández-González, S. (2020). Análisis exhaustivo de los principios de diseño en el contexto de Industria 4.0. Revista Iberoamericana de Automática e Informática Industrial, 17(4), 432-447. https://doi.org/10.4995/riai.2020.12579Bonilla, I., Reyes, F., & Mendoza, M. (2005). Modelling and simulation of a wheeled mobile robot in configuration classical tricycle. In 5th WSEAS International Conference on Instrumentation, Measurement, Control, Circuits and Systems. Cancún, México.Espinosa, F., Santos, C., & Sierra-García, J. E. (2021). Transporte multi-AGV de una carga: estado del arte y propuesta centralizada. Revista Iberoamericana de Automática e Informática industrial, 18(1), 82-91. https://doi.org/10.4995/riai.2020.12846Galasso, F., Rizzini, D. L., Oleari, F., & Caselli, S. (2019). Efficient calibration of four wheel industrial AGVs. Robotics and Computer-Integrated Manufacturing, 57, 116-128. https://doi.org/10.1016/j.rcim.2018.11.005García, J. M., Valero, A., & Bohórquez, A. (2020). Efecto de la suspensión en la estabilidad al vuelco y direccionamiento de robots moviéndose sobre discontinuidades de terreno. Revista Iberoamericana de Automática e Informática industrial, 17(2), 202-214. https://doi.org/10.4995/riai.2020.12308Guney, M. A., & Raptis, I. (2020). Dynamic prioritized motion coordination of multi-AGV systems. Robotics and Autonomous Systems, 103534. https://doi.org/10.1016/j.robot.2020.103534Han, K., Choi, M., & Choi, S. B. (2018). Estimation of the tire cornering stiffness as a road surface classification indicator using understeering characteristics. IEEE Transactions on Vehicular Technology, 67(8), 6851-6860. https://doi.org/10.1109/TVT.2018.2820094Landau, L. D., & Lifshitz, E. M. (2013). Course of theoretical physics. Elsevier.Li, G., Lin, R., Li, M., Sun, R., & Piao, S. (2019). A master-slave separate parallel intelligent mobile robot used for autonomous pallet transportation. Applied Sciences, 9(3), 368. https://doi.org/10.3390/app9030368Markets and markets 2021. (https://www.marketsandmarkets.com/MarketReports/automated-guided-vehicle-market-27462395.html)Madrigal Moreno, S. A., & Muñoz Ceballos, N. D. (2019). Vehículos de guiado autónomo (AGV) en aplicaciones industriales: una revisión. Revista Politécnica, 15(28), 117-137. https://doi.org/10.33571/rpolitec.v15n28a11Niestrój, R., Rogala, T., & Skarka, W. (2020). An Energy Consumption Model for Designing an AGV Energy Storage System with a PEMFC Stack. Energies, 13(13), 3435. https://doi.org/10.3390/en13133435Nguyen, H. H., Nguyen, T. T., Nguyen, T. T., & Phan, H. L. (2020, December). Kinematic Model Reference Adaptive Controller for a Lurking Type Automated Guided Vehicle using Traction Drive Unit. In 2020 International Conference on Advanced Mechatronic Systems (ICAMechS) (pp. 108-112). IEEE.Sierra, J. E., & Santos, M. (2018). Modelling engineering systems using analytical and neural techniques: Hybridization. Neurocomputing, 271, 70-83. https://doi.org/10.1016/j.neucom.2016.11.099Sierra-García, J. E., & Santos, M. (2020a). Mechatronic modelling of industrial AGVs: A complex system architecture. Complexity, Article ID 6687816, 2020. https://doi.org/10.1155/2020/6687816Sierra-García, J. E., & Santos, M. (2020b, September). Control of Industrial AGV Based on Reinforcement Learning. In International Workshop or Soft Computing Models in Industrial and Environmental Applications (pp. 647-656). Springer, Cham. https://doi.org/10.1007/978-3-030-57802-2_62Smieszek, M., Dobrzanska, M., & Dobrzanski, P. (2019). The impact of load on the wheel rolling radius and slip in a small mobile platform. Autonomous Robots, 43(8), 2095-2109. https://doi.org/10.1007/s10514-019-09857-0Smieszek, M., Dobrzanska, M., & Dobrzanski, P. (2020). Measurement of wheel radius in an automated guided vehicle. Applied Sciences, 10(16), 5490. https://doi.org/10.3390/app10165490Statista 2021 (https://www.statista.com/statistics/882696/global-agv-marketvolume/#:~:text=In%202018%2C%20it%20was%20estimated,e%2Dcommerce%20companies%20and%20hospitals ).Suárez, J. I., Vinagre, B. M., Gutiérrez, F., Naranjo, J. E., & Chen, Y. Q. (2004, July). Dynamics models of an AGV Based on Experimental Results. In Proc. of the 5th IFAC Symposium on Intelligent Autonomous Vehicles. https://doi.org/10.1016/S1474-6670(17)31987-0Veiga, J., Sousa, J., Machado, J., Mendonça, J., Machado, T., & Silva, P. (2019, April). Modeling of Dynamic Behavior of AGV systems. In 2019 6th International Conference on Control, Decision and Information Technologies (CoDIT) (pp. 1307-1312). IEEE. https://doi.org/10.1109/CoDIT.2019.8820528Villagra, J., & Herrero-Pérez, D. (2011). A comparison of control techniques for robust docking maneuvers of an AGV. IEEE Transactions on Control Systems Technology, 20(4), 1116-1123. https://doi.org/10.1109/TCST.2011.2159794Weckx, S., Vandewal, B., Rademakers, E., Janssen, K., Geebelen, K., Wan, J.,... & van Nunen, E. (2020). Open Experimental AGV Platform for Dynamic Obstacle Avoidance in Narrow Corridors. In 2020 IEEE Intelligent Vehicles Symposium (IV) (pp. 844-851). IEEE. https://doi.org/10.1109/IV47402.2020.9304749Wu, X., Sun, C., Zou, T., Xiao, H., Wang, L., & Zhai, J. (2019). Intelligent path recognition against image noises for vision guidance of automated guided vehicles in a complex workspace. Applied Sciences, 9(19), 4108. https://doi.org/10.3390/app9194108Yuan, Z., Yang, Z., Lv, L., & Shi, Y. (2020). A Bi-Level Path Planning Algorithm for Multi-AGV Routing Problem. Electronics, 9(9), 1351. https://doi.org/10.3390/electronics9091351Yun, D. U. (2016). Kinematics and Dynamic Modeling and Simulation Analysis of Three-wheeled Mobile Robot. 2016 MDM International Conference on Mechanics Design, Manufacturing and Automation.Zhang, J., & Liu-Henke, X. (2020, July). Model-based design of the vehicle dynamics control for an omnidirectional automated guided vehicle (agv). In 2020 International Conference Mechatronic Systems and Materials (MSM) (pp. 1-6). IEEE. https://doi.org/10.1109/MSM49833.2020.920224

Design of a speed control using neural networks and genetic algorithms for autonomous vehicles

[Resumen] Los Vehículos Autónomos Guiados (AGV) son cada vez más populares en lo que a logística interna de las fábricas se refiere debido a su capacidad para transportar cargas pesadas y su alto grado de autonomía. No obstante, la dinámica de estos robots puede sufrir cambios debido a variaciones en la carga que transportan y/o a desgaste mecánico, lo cual implica una mayor complejidad en el control de velocidad. En muchas ocasiones se emplean controladores de tipo Proporcional Integral (PI) para dicho control. Sin embargo, este controlador exige un ajuste fino y carece de suficiente robustez ante variaciones de sus condiciones de trabajo. Con el fin de mejorar el rendimiento del control de velocidad, en este artículo se presenta el diseño de un neuro-controlador. Dado que encontrar unos valores óptimos para los hiperparámetros de aprendizaje puede ser difícil y requiere múltiples pruebas y ajustes, se opta por utilizar un Algoritmo Genético (AG) para buscar una solución válida de entre las óptimas.[Abstract] Autonomous Guided Vehicles (AGVs) are becoming increasingly popular in terms of internal factory logistics due to their ability to transport heavy loads and their high degree of autonomy. Nevertheless, the dynamics of these robots can undergo changes due to variations in their load and/or mechanical wear, which involves greater complexity in their speed control. Proportional Integral (PI) controllers are often used for this control. However, this controller requires fine tuning and lacks enough robustness against variations in working conditions. In order to improve the speed control performance, this article presents the design of a neuro-controller. Since finding optimal values for the learning hyperparameters can be difficult and requires multiple tests and adjustments, a Genetic Algorithm (GA) is used to find a valid solution among all the optimal

Fuzzy system for supporting the velocity envelope of an aircraft

[Resumen] Este artículo presenta un sistema inteligente basado en lógica borrosa para automatizar acciones de piloto de un avión comercial en las diferentes fases de vuelo a la hora de adecuar la envolvente de velocidad y mantenerse dentro de ella. Para ello se diseña un sistema modular simplificado que realiza la acción de cambio de la posición de las superficies de híper-sustentación (flaps y slats) de la aeronave según sus necesidades de velocidad, para mantener la envolvente de la aeronave, lo cual es crítico para la seguridad operacional del vuelo. De esta forma, la sustentación necesaria para el vuelo se mantiene a pesar de los cambios necesarios de velocidad a la requerida para las distintas fases (despegue, ascenso, crucero, aproximación y aterrizaje) como lo haría un piloto humano, pero de forma automática. Los resultados de la simulación en escenarios simplificados muestran el comportamiento esperado.[Abstract] This work presents an intelligent system, based on fuzzy logic, to automate the actions of a commercial airplane pilot in the different flight phases in order to adapt the speed envelope and stay within it. For this, a simplified modular system is designed that performs the action of changing the position of the high-lift surfaces (flaps and slats) of the aircraft according to its speed needs, trying to maintain the envelope of the aircraft, which is critical for flight safety. In this way, the lift necessary for the flight is maintained despite the necessary changes in speed to that required for the different phases (takeoff, climb, cruise, approach and landing) as a human pilot would do, but automatically. The simulation results in simplified scenarios show the expected behavior

The origins of Valdepeñas (Ciudad Real): the roman vicus and the medieval deserted Aberturas. Historical and archaeological research in La Mancha

Con motivo de la ejecución de obras en la autovía A4 han sido descubiertos e investigados elementos arqueológicos muebles e inmuebles en el yacimiento de Aberturas (Valdepeñas, Ciudad Real). Los materiales recuperados ponen de manifiesto la existencia de un extenso vicus de aproximadamente 24 hectáreas fundado en la segunda mitad del siglo III d.C. Este asentamiento ha tenido un largo recorrido histórico desde entonces hasta hoy. En ese lugar se han desarrollado las poblaciones de Aberturas (denominación medieval y moderna), Consolación (denominación moderna y contemporánea) y Villanueva de Franco (denominación contemporánea). Además de viviendas y materiales arqueológicos cerámicos romanos, medievales -tanto islámicos como cristianos- y modernos, la intervención arqueológica ha permitido documentar silos, varios de los cuales fueron hallados vacíos y cerrados. También se han encontrado un pozo antiguo que explotaba el Acuífero 23, piletas, un lagar y el locus de otroOn the occasion of works on the A4 Highway have been discovered and researched an archaeological site at Aberturas (Valdepeñas, Ciudad Real). Recovered materials reveal the existence of a large vicus with approximately 24 hectares, founded in the second half of the third century AD. This settlement has had a long history since then until today, because of the development of populations called Aberturas (the medieval and modern name), Consolation (the modern and contemporary name) or Villanueva de Franco (the contemporary name). The archaeological intervention let document houses, pottery, glass, silos -several of these empty and closed-, a well, pools, a winery and a locus of another on

Long-Term Clinical Study of Implants Placed in Maxillary Sinus Floor Augmentation Using Beta-Tricalcium Phosphate

Introduction. The aim of this study was to show the long-term clinical outcomes of implants placed in maxillary sinus floor augmentation (MFSA) using beta-tricalcium phosphate (β-TCP). Patients and methods. Maxillary patients were diagnosed for MFSA and used beta- β-TCP. After the lateral sinus surgery, implants were loaded at 6 months with restorations. The clinical follow-up was at 10 years. Results. One hundred and one patients (58 females and 43 males) were treated with MFSA. Twenty-nine patients (28.7%) had a history of periodontitis. Thirty-three patients (32.7%) were smokers. One hundred and twenty-one MFSA, 81 unilateral and 20 bilateral sites, with 234 implants were performed. The average vertical bone height available was 4.92 ± 1.83 mm. The average vertical bone gain obtained was 6.95 ± 2.19 mm following MFSA. The implant cumulative survival rate was 97.2%. Three implants (1.3%) were lost during the healing period. Six implants (2.6%) were lost by peri-implantitis. One hundred and fifteen restorations were placed in the patients. Mean marginal bone loss was 1.93 mm ± 1.03 mm. Six patients (27.3%) showed technical complications. Thirty-six implants (15.3%) in 14 patients (13.9%) were associated with peri-implantitis. Conclusions. This study indicates that treatment with implant-supported restoration by MFSA using β-TCP constitutes a successful implant approach

Application of the Delphi Method for Content Validity Analysis of a Questionnaire to Determine the Risk Factors of the Chemsex

Chemsex is understood as 'the intentional use of stimulant drugs to have sex for an extended time among gay, bisexual, and other men who have sex with men'. It is a public health problem because of the increased incidence of cases and because of the consequences on the physical and mental health of those who practice it. Aim: This study aimed to analyze, with the help of the Delphi method, the content validity of a new instrument to assess the risk of behaviors associated with the chemsex phenomenon. Method: First, a bank of items identified from the literature was elaborated. Secondly, 50 experts with knowledge of the chemsex phenomenon at the national level were contacted. A Delphi group was formed with them to carry out two rounds of item evaluation. The linguistic evaluation (comprehension and appropriateness) was assessed using a Likert scale from 1 to 5 for each item. Items that did not reach a mean score of 4 were eliminated. Content assessment was calculated using each item's content validity index (CVI) and Aiken's V (VdA). A minimum CVI and VdA value of 0.6 was established to include the items in the questionnaire. Results: A total of 114 items were identified in the literature. In the first round of Delphi evaluation, 36 experts evaluated the items. A total of 58 items were eliminated for obtaining a CVI or VdA of less than 0.6, leaving 56 items. In a second Delphi round, 30 experts re-evaluated the 56 selected items, where 4 items were eliminated for being similar, and 10 items were also eliminated for not being relevant to the topic even though they had values higher than 0.6, leaving the scale finally composed of 52 items. Conclusion: A questionnaire has been designed to assess the risk of behaviors associated with the chemsex phenomenon. The items that make up the questionnaire have shown adequate content and linguistic validity. The Delphi method proved to be a helpful technique for the proposed objective