The effects of surface defects (oxygen vacancies) on the electronic structure and photoluminance properties titanium doped ZnO nanoparticles are reported. Nanoparticles different sizes ranging from 6 to 25 nm characterized by x-ray diffraction, Transmission electron microscopy, photoemission spectroscopy, photoluminescence (PL) spectra. Structural analysis indicates that Ti ions substituted at Zn sites in matrix. Surface systemically increasing with decreasing particles size, which is also...

The phenomenon of dynamic soaring, as exhibited by soaring birds, has long been a biological inspiration for aerospace and control engineers. If this fascinating phenomenon, which allows birds to perform almost unpowered flight using wind shear, can be mimicked unmanned aerial vehicles (UAVs), then there is substantial potential technological economic enhancement UAV performance. Although considerable amount research covering the modeling, optimization, simulation aspects different UAVs...

View Video Presentation: https://doi.org/10.2514/6.2022-0881.vid Dynamic soaring as exhibited by birds is an engineless flight mode that utilizes energy available in the horizontal wind shear. Realizing immense potential of dynamic soaring, efforts were made to incorporate into navigation algorithm UAVs. Although a considerable amount research covering optimization, control, and simulation aspects UAVs performing performed, there little nonconclusive work analyzing stability such about...

Friction welding is one of the foremost processes for similar and dissimilar metals. Previously, process has been modeled utilizing rudimentary techniques constant friction slip-stick friction. The motivation behind this article to present a new characteristic temperature profile estimation in modeling rotary process. For first time, unified model exhibited, with an implementation phase transformation materials. was generated on COMSOL Multiphysics® thermal structural modules were used plot...

ABSTRACT This paper presents an open framework, through which, conventional general purpose aerial munitions can be converted into smart munitions. The retrofit consists of a adaptation kit (SAK) having dedicated Guidance and Control Module (GCM). along with the GCM ensures that SAK glide optimally towards designated target. To reduce cost, number control surfaces has been kept to bare minimum, which resulted in under actuated system. methodology proposed utilises theory gain-scheduled leads...

Typical challenges of supersonic flight include wave drag, acoustic signature, and aerodynamic heating due to the formation shock waves ahead vehicle. Efforts in form sleek designs, better propulsion systems, implementation passive active techniques are generally adopted achieve a weaker system. Shock reduction can improve range, reduce fuel consumption, provide thermal protection forebody region. This paper briefly reviews techniques, including passive, active, hybrid flow control. Airfoil...

<div>This study presents a novel reinforcement learning (RL)-based control framework aimed at enhancing the safety and robustness of quadcopter, with specific focus on resilience to in-flight one propeller failure. This addresses critical need robust strategy for maintaining desired altitude quadcopter save hardware payload in physical applications. The proposed investigates two RL methodologies, dynamic programming (DP) deep deterministic policy gradient (DDPG), overcome challenges...

This study investigates the combustion dynamics of methane in a dual swirl combustor, focusing on improving efficiency and understanding flow features. Methane, as conventional fuel, offers high energy content relatively low carbon emissions compared to other hydrocarbons, making it promising choice for sustainable solutions. Accurate numerical models are essential optimization processes, particularly design engines utilizing methane. In this work, we employ partially premixed model based...

Dynamic soaring is a process of acquiring energy available in atmospheric wind shears and commonly exhibited by birds to perform long distance flights. This paper aims demonstrate viable algorithm which can be implemented near real time environment formulate optimal trajectories for dynamic maneuvers small scale Unmanned Aerial Vehicle (UAV). The objective harness maximum from atmosphere shear improve loiter Intelligence, Surveillance Reconnaissance (ISR) missions. Three-dimensional...

In this paper, we present dynamic modelling and stability analysis of a generic UAV in the glide phase under engine failure condition. When such extreme phenomena occurs, most desirable requirement is to survive that stage by keeping vehicle controllable maintaining its orientation towards intended direction with maximum extended range. This study investigates aspects one aerial proposed architecture, six degree freedom simulation model implemented through set coupled non-linear differential...

A = disc area of the propeller D drag g acceleration due to gravity J cost/objective function L lift L=W lift-to-weight ratio m mass aircraft T thrust Tmax maximum T=W thrust-to-weight max u horizontal velocity control variable vector ut terminal V freestream wi ith weight coefficient vt vertical W w induced aft x yi altitude at discretized calculation instant z fus fuselage and inboard wing angle attack prop outboard _ rate change flight-path air density , d dt

Virtual reality (VR) is in its nascent technological advancement and market diffusion stages. Interestingly, the scientific exploration concerning impact of non-isometric mapping disparities within visual–vestibular stimuli on motion sickness remains deficient. This investigation focuses scrutinizing implications for context flight simulation. The developed platform, offering specific pitch roll ranges ±16 ±17 degrees, respectively, was employed to induce varying ratios simulated cues....