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UAV Lateral Path Following: Nonlinear Sliding manifold for Limited Actuation

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UAV Lateral Path Following: Nonlinear Sliding Manifold for L...

第36届中国控制会议

作者： Syed Ussama Ali Raza Samar m.zamurad shah Center of Excellence in Science and Applied Technologies (CESAT)

ISBN: (纸本)9781538629185

The lateral guidance objective is to derive the cross track error towards zero with graceful and stable maneuvers and then to keep it as minimum as possible. A nonlinear sliding surface based lateral guidance scheme is proposed here for Unmanned Aerial Vehicles(UAVs) application with limited actuation. Following the inner(control) and outer(guidance)loop structure, the proposed guidance scheme resides in outer loop and generates reference bank angle commands for the inner control loop. The proposed 1 order SmC algorithm based on nonlinear sliding surface is derived using the kinematic equations for bank-to-turn vehicles. mathematical proof of existence of sliding mode and actuation boundedness of the closed-loop is also provided. The proposed guidance and control system performance is verified via simulation results for different scenario. A high fidelity nonlinear 6-degrees-offreedom(6-dof) scaled Yak-54 UAV mathematical model is used for flight simulations. Simulation results validated the effectiveness and performance of the proposed lateral guidance scheme.

关键词： Stability analysis Unmanned aerial vehicles manifolds Actuators mathematical model Sliding mode control Robustness

Adaptive Sliding mode Roll Control of a Canard-Controlled missile

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Adaptive Sliding Mode Roll Control of a Canard-Controlled Mi...

2010 Chinese Control and Decision Conference

作者： m.zamurad shah Raza Samar A.I.Bhatti mohammad Ali Jinnah University IslamabadPakistan

This work is meant to design a roll controller for a short range missile with a free-spinning tail using the sliding mode control *** canards located near the nose of the missile provide aerodynamic ***/yaw stability is achieved through four rotating fins located at the tail of the *** of the missile dictates the whole trajectory in the atmosphere where dynamic pressure varies between 0 and 7 *** the missile can be fired at different launch angles,which implies that the profile of dynamic pressure is not *** strategy strongly depends on dynamic pressure in the case of canard-controlled *** the case of varying dynamic pressure,design of a robust roll controller that can keep roll angle near zero is a challenging *** this paper,a roll controller is designed for a canard-controlled short range missile using sliding mode control *** is done in some control parameters to cater the variation in dynamic pressure and different launch *** robustness of the roll controller is tested in the presence of aerodynamic and other *** is established that the proposed roll controller is capable of rejecting aerodynamic and other disturbances and keep the roll angle close to zero.

关键词： missile sliding mode control adaptive control autopilot aerodynamics canards.

Robust Nonlinear Control Design For Scaled Yak-54 Unmanned Aerial Vehicle

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Robust Nonlinear Control Design For Scaled Yak-54 Unmanned A...

第26届中国控制与决策会议

作者： Ussama Ali m.zamurad shah Aamer Iqbal Bhatti Raza Samar Faculty of Electronic Engineering Mohammed Ali Jinnah University

In this work, the authors consider the applications of sliding mode controllers to the longitudinal flight dynamics of the benchmark system of scaled Yak-54 Unmanned Aerial Vehicle for executing maneuvers over full flight *** of unmanned aerial vehicle involves the problem of incomplete measurements, modeling uncertainties and external disturbances. Sliding mode control provides good precision and robustness to the aforementioned factors. First order sliding mode controller are designed but they provide chattering at the control input thus a non linear second order super twisting controller is used to provide chattering free control with improved performance for the robust stabilization of pitch angle and control of its altitude. The simulation results indicate good tracking and regulation control of the vehicle.

关键词： Sliding mode Control SmC Higher Order Sliding mode Control HOSm Strong Reachability Condition SRC

C-phycocyanin shows neuroprotective effect against rotenone-induced Parkinson’s disease in mice

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Asian Pacific Journal of Tropical Biomedicine 2024年第7期14卷 279-287页

作者： Hritik Rathod Ritu m.Soni Jigna S.shah Department of Pharmacology Institute of Pharmacy Nirma UniversityAhmedabadGujaratIndia

Objective:To investigate the neuroprotective effect of C-phycocyanin in a mouse model of rotenone-induced Parkinson’s ***:C-phycocyanin(50 mg/kg,i.p.,daily)was administered to rotenone(30 mg/kg,p.o.,daily)treated mice for 28 *** studies(Y-maze,rotarod,round beam walk,and wire-hang tests)were carried out to assess neurobehavioral *** and malondialdehyde were determined in both serum and striatal *** proteins(AKT,AmPK,NF-κB,BDNF,and alpha-synuclein)in the striatum were estimated using *** analyses(hematoxylin and eosin stainning as well as Nissl staining)were carried out to assess structural abnormalities in the ***:C-phycocyanin significantly increased BDNF levels and decreased alpha-synuclein *** also slightly upregulated AmPK and AKT levels without significant difference compared with the rotenone ***,rotenone-induced elevated oxidative stress and structural abnormalities in the striatum were markedly mitigated by ***:C-phycocyanin might have potential neuroprotective effects against Parkinson’s *** studies are warranted to verify its efficacy and to understand the molecular mechanisms behind the neuroprotective effects of C-phycocyanin in Parkinson’s disease.

关键词： Parkinson’s disease C-phycocyanin Alphasynuclein BDNF Oxidative stress Rotenone

Cooperative THz communication for UAVs in 6G and beyond

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Green Energy and Intelligent Transportation 2024年第1期3卷 25-31页

作者： Nazifa mustari muhammet Ali Karabulut A.F.m.shahen shah Ufuk Tureli Department of Electronics and Communication Engineering Yildiz Technical UniversityTurkey Department of Electrical Electronics Engineering Faculty of Engineering and ArchitectureKafkas UniversityKarsTurkey

One of the key components of any smart city is considered to be its intelligent transportation systems(ITSs).Unmanned aerial vehicles(UAVs)are envisioned in several ITS application fields because of their autonomous operation,mobility,communication/processing capabilities,and other *** this paper,cooperative terahertz(THz)communication is proposed for flying ad hoc networks(FANETs),which is a particular kind of network made up of a collection of small UAVs linked in an ad hoc fashion and working together to accomplish high-level *** frequency spectrum for wireless communication has been expanding continuously in order to meet the demand for *** the forthcoming 6G and beyond,communications in the THz range will be vital,similar to how mmWave-band communications are currently influencing the 5G of wireless mobile *** finite state machine(FSm)of the proposed cooperative communication system for THz band is presented.A markov chain model-based analytical study is carried out,which derives relationships among ***,numerical results are provided to support the analytical study.

关键词： Cooperative mAC THz UAVs 6G

Twinning aspects and their efficient roles in wrought mg alloys:A comprehensive review

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Journal of magnesium and Alloys 2024年第6期12卷 2201-2230页

作者： S.S.A.shah manping Liu Azim Khan Farooq Ahmad m.R.Abdullah Xingquan Zhang Shiwei Xu Zhen Peng School of materials Science and Engineering Jiangsu UniversityZhenjiang 212013China School of mechanical Engineering Anhui University of TechnologyMáanshan 243002China College of mechanical and Vehicle Engineering Hunan UniversityChangsha 410082China

Twinning is widely recognized as an effective and cost-efficient method for controlling the microstructure and properties of wrought magnesium(mg)***,twins play a crucial role in initiating dynamic recrystallization(DRX),while twin regions experience rapid recrystallization during static recrystallization(SRX).The activation of twinning can lead to changes in lattice orientation,significantly impacting the final texture in mg *** active roles of twinning are influenced by various factors during the activation process,and the mobility of twin boundaries(TB)can be amplified by stress effects,dislocation interactions,and thermal ***,annealing treatments that involve proper segregation or precipitation on TBs serve to stabilize them,restraining their *** such as segregation may also alter the twinning propensity in magnesium-rare earth(mg-RE)***{10–11}contraction twins(CT)and{10–11}-{10–12}double twins(DT)can promote dynamic recrystallization(DRX),they also pose a risk as potential sources of voids and ***,understanding the nucleation and growth mechanisms of twinning is crucial,and these aspects are briefly reviewed in this *** the factors mentioned above,this article summarizes the recent research progress in this field,shedding light on advancements in recent eras.

关键词： mg alloys Twinning Recrystallization Texture mechanical properties

morphology-Tailored Dynamic State Transition in Active-Passive Colloidal Assemblies

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Research 2024年第3期2024卷 751-760页

作者： Nan Yu Zameer H.shah mingcheng Yang Yongxiang Gao Institute for Advanced Study Shenzhen University518060ShenzhenChina Key Laboratory of Optoelectronic Device and Systems of ministry of Education and Guangdong Province College of Optoelectronic EngineeringShenzhen University518060ShenzhenChina Beijing National Laboratory for Condensed matter Physics and Laboratory of Soft matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Songshan Lake materials Laboratory DongguanGuangdong 523808China.

mixtures of active self-propelled and passive colloidal particles promise rich assembly and dynamic states that are beyond reach via equilibrium ***,controllable transition between different dynamic states remains ***,we reveal a plethora of dynamic behaviors emerging in assemblies of chemically propelled snowman-like active colloids and passive spherical particles as the particle shape,size,and composition are *** example,assembles of one or more active colloids with one passive particle exhibit distinct translating or orbiting states while those composed of one active colloid with 2 passive particles display persistent“8”-like cyclic motion or hopping between circling states around one passive particle in the plane and around the waist of 2 passive ones out of the plane,controlled by the shape of the active colloid and the size of the passive particles,*** morphology-tailored dynamic transitions are in excellent agreement with state diagrams predicted by mesoscale dynamics *** work discloses new dynamic states and corresponding transition strategies,which promise new applications of active systems such as micromachines with functions that are otherwise impossible.

关键词： Transition otherwise transitions

Al^(3+) doped CeO_(2) for proton conducting fuel cells

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International Journal of minerals,metallurgy and materials 2024年第10期31卷 2253-2262页

作者： Sarfraz shahzad Rasool muhammad Khalid mAKYousaf shah Bin Zhu Jung-Sik Kim muhammad Imran Asghar Nabeela Akbar Wenjing Dong Jiangsu Provincial Key Laboratory of Solar Energy Science and Technology/Energy Storage joint Research Center School of Energy and EnvironmentSoutheast UniversityNanjing 210096China School of microelectronics Hubei UniversityWuhan 430062China Sino-French Engineer School/School of General Engineering Beihang UniversityBeijing 100191China Renewable Energy Technologies Group Faculty of Engineering and Natural SciencesTampere UniversityFI-33014Finland

Developing high ionic conducting electrolytes is crucial for applying proton-conducting fuel cell(PCFCs)*** cur-rent study investigates the effect of alumina on the structural,morphological,electrical,and electrochemical properties of CeO_(2).Lattice oxygen vacancies are induced in CeO_(2) by a general doping concept that enables fast ionic conduction at low-temperature ranges(300-500℃)for *** refinement of the X-ray diffraction(XRD)patterns established the pure cubic fluorite structure of Al-doped CeO_(2)(ADC)samples and confirmed Al ions’fruitful integration in the CeO_(2) *** electronic structure of the alumina-doped ceria of the materials(10ADC,20ADC,and 30ADC)has been *** a result,it was found that the best composition of 30ADC-based electrolytes induced maximum lattice oxygen *** corresponding PCFC exhibited a maximum power output of 923 mW/cm^(2)at 500℃.moreover,the investigation proves the proton-conducting ability of alumina-doped ceria-based fuel cells by using an oxide ion-blocking layer.

关键词： proton ceramic fuel cells oxygen vacancies higher fuel cell performance doping fast ions transportation

Ir single atoms on NiFeZn-LDH matrix for exceptional oxygen evolution reaction

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Nano Research 2024年第8期17卷 7039-7044页

作者： muhammad Israr muhammad Humayun Jiaqi Zhang Khadim shah Xin Tan Chen Chen Yadong Li Department of Chemistry Tsinghua UniversityBeijing 100084China Energy Water and Environment LabCollege of Humanities and SciencePrince Sultan UniversityRiyadh11586Saudi Arabia

To address the sluggish kinetics of the oxygen evolution reaction(OER),a potential approach is to rationally design and fabricate extremely effective single atom catalysts(SACs).Using an appropriate matrix to stabilize single-atom active centers with optimal geometric and electronic structures is crucial for enhancing catalytic ***,we report the design and fabrication of Ir single atoms on NiFeZn layered double hydroxide(Ir-SAC/NiFeZn-LDH)electrocatalyst for highly efficient and stable *** is investigated that the NiFeZn support exhibits abundant defect sites and unsaturated coordination *** sites function to anchor and stabilize single Ir single atoms on the *** strong synergetic electronic interaction between the Ir single atoms and the NiFeZn matrix resulted in remarkable OER performance of the as-fabricated Ir-SAC/NiFeZn *** a loading Ir content of 1.09 wt.%,this catalyst demonstrates a highly stable OER activity,with an overpotential of 196 mV at 10 mA·cm^(−2) and a small Tafel slope of 35 mV·dec^(−1) for the OER in a 1 m KOH *** results significantly surpass the performance of the commercially available IrO_(2) catalyst.

关键词： Ir single atoms layered double hydroxides rational design geometric optimization oxygen evolution reaction