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19th International Conference on Electrical engineering, Computing Science and Automatic Control, CCE 2022

作者： Contreras-Torres, G.A.S. Garcia-Rodriguez, R. Dominguez-Mayorga, C.R. Espinoza, E.S. Upmh Postgraduate Program in Aerospace Engineering Mexico UMI-LAFMIA Cinvestav Conacyt Mexico

ISBN: (数字)9781665455084

ISBN: (纸本)9781665455084

In recent years, many companies and research groups have been developing the design and control of Blended Wing Body aircraft. Although commercial flights are unavailable today, the first flight is expected in the upcoming years. The Blended Wing Body configuration incorporates many advantages in security, maneuverability, fuel economy, and internal payload, to mention a few. This paper presents the aerodynamic design and control of the Mexican Blended Wing-Body aircraft, EHEKATL. The aerodynamic coefficients are obtained using XFLR5 for a specific flight condition to guarantee static longitudinal stability. Assuming that some aerodynamics coefficients and parameters of the EHEKATL BWB are unknown, an adaptive Backstepping controller for cruise flight is proposed. Stability conditions to guarantee asymptotically convergence of tracking errors are shown. Finally, numerical simulation results, under many conditions, show the satisfactory performance of the proposed approach during cruise phase flight. © 2022 IEEE.

关键词： Aircraft control

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Damping Injection Learning for Robots with Actor-Critic Driven by Integral Sliding Manifolds 20

Damping Injection Learning for Robots with Actor-Critic Driv...

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20th International Conference on Electrical engineering, Computing Science and Automatic Control, CCE 2023

作者： Tevera-Ruiz, Alejandro Garcia-Rodriguez, Rodolfo Parra-Vega, Vicente Robotics and Advanced Manufacture-CINVESTAV Saltillo Mexico Univ. Politécnica Metropolitana de Hidalgo Postgraduate Program in Aerospace Engineering Mexico

ISBN: (纸本)9798350306767

Reinforcement Learning (RL) is characterized by enforcing a reward collection mechanism that qualifies task performance aimed at optimizing a value function that tunes the action (control). In contrast to control theory, RL satisfies two metrics simultaneously: the task metric commonly, defined as the task error, and the temporal difference (TD) error. Thus, the RL has been empowered to learn how to fulfill control tasks based on a learning stage that collects rewards that evaluate a second metric of the robot's performance. In this way, including RL in control systems is an advantageous scheme for some critical tasks nowadays. Consequently, the stability can be guaranteed, largely missing in the RL's literature, to safe system operation.. In this paper, we propose an Actor-Critic (AC) scheme using the Critic Neural Network (C-NN) to approximate a value function using the TD error reduction, whereas the adaptive tuning of damping injection gain is provided by the Actor NN (A-NN) to enforce stability in closed-loop finally;achieving asymptotic stability with an underlying integral sliding mode loop. In this way, our proposal contributes to a novel model-free RL scheme that yields local exponential convergence with a smooth control action. Numeric simulations for a 2-DoF robot manipulator are presented and discussed under different conditions.. © 2023 IEEE.

关键词： Asymptotic stability

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Actor-Critic Learning of Variable Damping Injection for Quadrotor Attitude Robust Control 20

Actor-Critic Learning of Variable Damping Injection for Quad...

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20th International Conference on Electrical engineering, Computing Science and Automatic Control, CCE 2023

作者： Tevera-Ruiz, Alejandro Urzúa-Correa, Sergio E. Parra-Vega, Vicente Sanchez-Orta, Anand Garcia-Rodriguez, Rodolfo CINVESTAV Robotics and Adv. Manufacturing Saltillo Mexico Univ. Politécnica Metropolitana de Hidalgo Postgraduate Program in Aerospace Engineering Mexico

ISBN: (纸本)9798350306767

On the one hand, a class of model-free integral sliding modes requires damping injection to stabilize the closed-loop system to a certain bound, [1]. This technique has been extended to a variety of robots, including quadrotors. However, the damping matrix K value is difficult to calculate precisely. Henceforth, it is customary to overestimate it in practice, which is ritical for airborne robots, such as a lightweight quadrotor, which leads to a higher rate of dissipation with higher energy expenditure, which is highly inefficient. On the other hand, novel Reinforcement Learning (RL) schemes have also been developed for autotuning feedback gains, mainly using Actor-Critic (AC)-RL architectures. In this paper, we synergistically blend both schemes to learn the necessary K that enables the enforcement of integral sliding modes to control of the attitude of the quadrotors. Local robust exponential tracking is achieved without any pre-training of neural networks neither of adaptive parameters nor any knowledge of dynamics. A representative comparative simulation study is presented that shows the effectiveness of our scheme versus the fixed-gain case. The results show how critical it is K to complete the flight mission without wasting energy, then less battery consumption, an essential by-product of our formulation. As a future work, an experimental testbed is under development to test it in soft real-time, including its extension to position tracking. © 2023 IEEE.

关键词： Robust control

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PLA/jute fabric laminate composites: influence of weight percentage on mechanical properties and fracture behavior

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Discover Mechanical engineering 2025年第1期4卷 1-15页

作者： Cabrera, Fabian Luna Arellano, Mauricio Torres Franco-Urquiza, Edgar Adrian Center for Engineering and Industrial Development Interinstitutional Postgraduate Program in Science and Technology Av. Pie de la Cuesta 702-No. 702 Desarrollo San Pablo Queretaro 76125 Mexico Center for Engineering and Industrial Development Aerospace Carretera Estatal 200 Km 23 Queretaro 76270 Mexico

Polylactic acid (PLA) is a widely studied and characterized bio-based polymer with biodegradable characteristics. Its use in environmentally friendly composite laminates is a recent field of research. In this work, we prepared eco-friendly PLA/Jute laminate composites and PLA flat sheets of 2 mm thickness using compression molding. Various experiments were performed to obtain composite plates with excellent quality. However, the successful configuration was the interleaved arrangement of PLA pellets/Jute fabrics stacking/PLA pellets. Scanning electron microscopy observations revealed no voids or delaminations, so the PLA pellets adequately impregnated the jute fiber fabrics. The number of jute fiber layers strongly influenced the mechanical properties of PLA. The stiffness of the composites increased progressively up to 145% compared to neat PLA, with an inverse behaviour in ductility, which decreased up to 60% in the composite with four layers of jute fiber fabrics. The strength did not show a clear trend and was attributed to the weight fraction of PLA. When the weight fraction is predominantly PLA, fracture occurs due to the brittleness of PLA, but when the weight fraction is mainly jute fiber, the tensile strength increases, and fracture occurs due to fiber failure. In all cases, PLA and the composites showed brittle behaviour. The storage modulus was noticeably improved by the stiffness provided by the jute fiber fabric layers, even above the glass transition temperature, where the thermomechanical properties of PLA were inferior. The trend in fracture behaviour shown by PLA/Jute laminates is almost the same as that previously observed in the mechanical behaviour under tension, indicating that the weight fraction strongly influences the impact strength of PLA/Jute composites. The impact strength of PLA decreased by approximately 39% in PLA/Jute-2 composite but increased up to 9% in PLA/Jute-4 laminate. The fracture surface of PLA neat differs from that of PLA/J

关键词： Fracture behavior Green composites Jute fibers Mechanical properties PLA

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RBF Neural Network Based on FT-Windows for Auto-Tunning PID Controller 21st

RBF Neural Network Based on FT-Windows for Auto-Tunning PI...

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21st Mexican International Conference on Artificial Intelligence, MICAI 2022

作者： Castro, O. F. Garcia Velasco, L. E. Ramos Navarrete, M. A. Vega Rodriguez, R. Garcia Mayorga, C. R. Domínguez Hernández, E. Escamilla Moreno, L. N. Oliva Postgraduate Program of Aerospace Engineering Metropolitan Polytechnic University of Hidalgo Mexico City Mexico ESIME Culhuacan National Polytechnic Institute Mexico City Mexico UPIIH Hidalgo National Polytechnic Institute Hidalgo Mexico

ISBN: (纸本)9783031194924

The weighted function windows are used in many areas as signal analysis and application systems. In addition, the weighted functions are broad uses in filter design where different windows allow to choose different filter characteristics. The most common individual window types are rectangular, Hanning, Flat Top, and Keiser-Bessel. This paper presents the Flat-Top Windows (FTW) applied to control systems where the FTW are used as activation functions on a radial basis neural network (RBF). Contrary to the "traditional" FT weighted function windows, where time windows limit the information, this paper proposes new ones that, including new parameters, allow translation and dilation of the window. Additionally, these new parameters are updated using a gradient descent algorithm. The new FTW is applied to the Quanser helicopter control where the RBF neural network is used for: a) the input-output identification of the system and b) auto-tuning PID controllers. Numerical simulation results are presented to show the system’s performance under different conditions. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.

关键词： Three term control systems

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Damping Injection Learning for Robots with Actor-Critic Driven by Integral Sliding Manifolds

Damping Injection Learning for Robots with Actor-Critic Driv...

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International Conference on Electrical engineering, Computing Science and Automatic Control (CCE)

作者： Alejandro Tevera-Ruiz Rodolfo Garcia-Rodriguez Vicente Parra-Vega Robotics and Advanced Manufacture-CINVESTAV Saltillo Mexico Postgraduate Program in Aerospace Engineering Univ. Politécnica Metropolitana de Hidalgo Mexico

Reinforcement Learning (RL) is characterized by enforcing a reward collection mechanism that qualifies task performance aimed at optimizing a value function that tunes the action (control). In contrast to control theory, RL satisfies two metrics simultaneously: the task metric commonly, defined as the task error, and the temporal difference (TD) error. Thus, the RL has been empowered to learn how to fulfill control tasks based on a learning stage that collects rewards that evaluate a second metric of the robot’s performance. In this way, including RL in control systems is an advantageous scheme for some critical tasks nowadays. Consequently, the stability can be guaranteed, largely missing in the RL’s literature, to safe system operation.. In this paper, we propose an Actor-Critic (AC) scheme using the Critic Neural Network (C-NN) to approximate a value function using the TD error reduction, whereas the adaptive tuning of damping injection gain is provided by the Actor NN (A-NN) to enforce stability in closed-loop finally; achieving asymptotic stability with an underlying integral sliding mode loop. In this way, our proposal contributes to a novel model-free RL scheme that yields local exponential convergence with a smooth control action. Numeric simulations for a 2-DoF robot manipulator are presented and discussed under different conditions..

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Actor-Critic Learning of Variable Damping Injection for Quadrotor Attitude Robust Control

Actor-Critic Learning of Variable Damping Injection for Quad...

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International Conference on Electrical engineering, Computing Science and Automatic Control (CCE)

作者： Alejandro Tevera-Ruiz Sergio E. Urzúa-Correa Vicente Parra-Vega Anand Sanchez-Orta Rodolfo Garcia-Rodriguez Robotics and Adv. Manufacturing CINVESTAV Saltillo Mexico Postgraduate Program in Aerospace Engineering Univ. Politécnica Metropolitana de Hidalgo Mexico

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In vivo study of conductive 3D printed PCL/MWCNTs scaffolds with electrical stimulation for bone tissue engineering

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Bio-Design and Manufacturing 2021年第2期4卷 190-202页

作者： Edney P.e Silva Boyang Huang Júlia V.Helaehil Paulo R.L.Nalesso Leonardo Bagne Maraiara A.de Oliveira Gabriela C.C.Albiazetti Ali Aldalbahi Mohamed El-Newehy Milton Santamaria-Jr Fernanda A.S.Mendonça Paulo Bártolo Guilherme F.Caetano Postgraduate Program in Biomedical Sciences University Center of Hermínio Ometto Foundation-FHOArarasSao PauloBrazil Department of Mechanical Aerospace and Civil EngineeringSchool of EngineeringUniversity of ManchesterManchester M139PLUK King Abdullah Institute for Nanotechnology King Saud UniversityRiyadh 11451Saudi Arabia

Critical bone defects are considered one of the major clinical challenges in reconstructive bone *** combination of 3D printed conductive scaffolds and exogenous electrical stimulation(ES)is a potential favorable approach for bone tissue *** this study,3D conductive scaffolds made with biocompatible and biodegradable polycaprolactone(PCL)and multi-walled carbon nanotubes(MWCNTs)were produced using the extrusion-based additive manufacturing to treat large calvary bone defects in *** results show that the use of PCL/MWCNTs scaffolds and ES contributes to thicker and increased bone tissue formation within the bone *** and mineralization are also significantly promoted using high concentration of MWCNTs(3 wt%)and ***,scaffolds favor the tartrate-resistant acid phosphatase(TRAP)positive cell formation,while the addition of MWCNTs seems to inhibit the osteoclastogenesis but present limited effects on the osteoclast functionalities(receptor activator of nuclear factor κβ ligand(RANKL)and osteoprotegerin(OPG)expressions).The use of ES promotes the osteoclastogenesis and RANKL expressions,showing a dominant effect in the bone remodeling *** results indicate that the combination of 3D printed conductive PCL/MWCNTs scaffold and ES is a promising strategy to treat critical bone defects and provide a cue to establish an optimal protocol to use conductive scaffolds and ES for bone tissue engineering.

关键词： Additive manufacturing Bone regeneration Bone remodeling Carbon nanotube Conductive scaffolds Electrical stimulation

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Progress in bio-fibers, bio-films, bio-polymers, and bio-composites for biobased food packaging via bibliometric approach

Food Chemistry Advances

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Food Chemistry Advances 2025年 6卷

作者： Santos, Thiago F. Santos, Caroliny M. Rao, H. Jeevan Sanjay, M.R. Nascimento, J.H.O. Souza, D.F.S. Gapsari, Femiana Raharjo, Rudianto Siengchin, Suchart Postgraduate Program in Chemical Engineering Technology Center Federal University of Rio Grande do Norte Av. Prof. Sen. Salgado Filho 3000 Rio Grande do Norte Natal 59072-970 Brazil Amity Institute of Aerospace engineering Amity University Uttar Pradesh Uttar Pradesh Noida India Natural Composites Research Group Lab Department of Materials and Production Engineering The Sirindhorn International Thai-German School of Engineering (TGGS) King Mongkut's University of Technology North Bangkok (KMUTNB) Bangkok Thailand Mechanical Engineering Department Faculty of Engineering Brawijaya University MT Haryono167 Malang 65145 Indonesia

This bibliometric study examines publications spanning from 1995 to 2023 on biobased materials for food-packaging (BMFP), often proposed as alternatives to petroleum-based on FP. The number of articles related to this topic exhibited an annual growth rate (AGR) of 105.7% from 2019 to 2023 compared to 1995 to 2018, indicating a growing interest in this field over the past 28 years, with 2082 articles published in high-impact journals. Notably, countries such as China, India, and Brazil demonstrate significant scientific output per capita, with influential groups based in institutions from Malaysia and Spain (Universiti Putra Malaysia, IATA, and CSIC). Among over 4,000 key-words, those with high co-occurrence were analyzed to identify crucial research areas and current knowledge gaps. Using the SC database, 1,233 articles from 2019 to 2023 were selected to explore the research landscape and key areas of interest within BMFP. Temporal keyword analysis revealed emerging themes, including active food packaging (AFP) and its antimicrobial capabilities, nanotechnology and composites in FP, biodegradability and edible-films, biopolymers for food-packaging, and pectin-based active packaging materials. Thus, eco-friendly food packaging solutions based on nanoparticles and polysaccharides show prospects for development or contribution to advancements. Consequently, the use of AFP demonstrates a prosperous trend for the food packaging-industry in the future. © 2025 The Author(s)

关键词： Active food packaging Chitosan Edible films Nanoparticles Tensile strength

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Thermal Degradation of Pan Fibers Modified with Hydrazine Hydrate and Strontium Ions

SSRN

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SSRN 2023年

作者： Cabral, Aluisio A. Soares, Drielle N.N. Júnior, Carlos A.R.B. Serbena, Francisco Carlos Postgraduate Program in Materials Engineering Federal Institute of Maranhão – IFMA MA São Luis65030-001 Brazil Department Aerospace Engineering Federal University of Maranhão – UFMA MA São Luís65080-805 Brazil Department of Physics State University of Ponta Grossa – UEPG PR Ponta Grossa84030-000 Brazil Department of Physics DEFIS Federal Institute of Maranhão – IFMA MA São Luís65030-001 Brazil

In this work, we added strontium ions to hydrolyzed PAN fibers to improve their thermal resistance. For comparison, we characterized hydrolyzed non-modified (PAN-H) and strontium-modified PAN fibers (PAN-H-Sr) by several techniques, such as XRD, FTIR, TG, DSC, and SEM. Our XRD diffractograms demonstrated that PAN-H-Sr was more crystalline, while the FTIR spectra confirmed that PAN textile fiber underwent hydrolysis by breaking nitrile group bonds, incorporating the refractory cation into the fiber through the O – Sr – O bond. SEM micrographs showed that the width of the PAN-H-Sr fiber decreased, and a stiffer structure was obtained. The TG and DSC analysis indicated that PAN-H-Sr presented higher thermal stability since the presence of strontium delayed the degradation reactions of PAN, with no visible melting of the material, and at the end of the heat treatment, exposed a more significant residual mass equivalent to 48.55%. © 2023, The Authors. All rights reserved.

关键词： Fourier transform infrared spectroscopy

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