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This manuscript presents the experimental study on low-cost sensor sensitivity of inspection quadcopter’s anti-collision system. This inspection quadcopter is designed to be operated in aerodrome or hanger for the inspection of wide body aircraft for lightning strikes. One of most important features that the inspection quadcopter must equipped with is anti-collision system. The anti-collision system will ensure the inspection quadcopter maintain a safe distance from the aircraft and other structures during the inspection process. As one of the project’s objectives is to design and develop an anti-collision system for the inspection quadcopter, it is aimed at developing using low-cost sensors and components. Experiments were done to choose the best low-cost sensor to be used as the rangefinder in the inspection quadcopter’s anti-collision system. The sensitivity of the low-cost sensors were tested by comparing the measured distance and the actual distance of obstacles. The percentage error reflects the sensitivity of the sensor under certain circumstances. The second objective of this research is integrating the best low-cost sensors the anti-collision system. The anti-collision system was programmed using Arduino IDE software. Lastly, the third object of this research, which is to experiment the performance of anti-collision system was achieved by performing the ground test on the anti-collision system of the inspection quadcopter. The performance of anti-collision was shown on the PWM correction signal generated by the anti-collision system. In conclusion, this paper shows the engineering approach on an industrial problem on developing an anti-collision system using low-cost sensors.

During the course of recent studies on wings at low Reynold number, it was observed that wing corrugation is often assumed to play an important role as well. However, studies show that corrugation of the wing is intended for structural purposes, and not aerodynamics. Corrugated wings have the advantage of being light and sturdy. Therefore, the main aim of this study is to understand the flow behaviour of the corrugated insect-scale wing; by conducting, a geometric parametric study during a non-oscillatory flight at a particular low Reynolds number and at two different angles of attack. In this computational study, a 3-D section of the corrugated wing along the chord is considered. The lattice Boltzmann method offers an alternative framework compared to the Navier-Stokes simulations. An open-source Parallel Lattice Boltzmann Solver on a high-performance computing platform is used for this computational analysis. The present study shows that the flow-related performance of the corrugated wing in terms of forces and kinetic energy is predominantly governed by the geometric variations that can largely affect the formation of vortices and their mutual interaction. The study reveals that the presence of corrugation does not affect the enhancement of forces and corrugation near the leading edge generally affects the performance due to large flow separation affecting the suction.

Increased environmental consciousness and demand for sustainable materials have encouraged the use of more renewable and environmentally acceptable resources as reinforcement, for the natural fiber like the (Pineapple Leaf Fiber) PALF and Kenaf fiber material. These materials are natural fiber which are environmental friendly and biodegradable. This environmental friendly resources has been a demand in all industries including the aerospace industry. So, this project is to develop a drone frame kit made up of natural fiber. There are very less studies on the drone frame kit made up of natural fiber. Drones are mostly made up of synthetic fiber which is not biodegradable. Three designs of the drone frame kit had been designed by Fusion 360 software where the best frame kit with least stress distribution, least total deformation and least strain will be chosen to develop the frame. Ansys simulation can be used to analyze the frame kits for the finite element analysis. In the Ansys simulation the static structural part had been chosen to make the analysis where few boundary conditions added, and the mesh dependency test was done to get the best result. PALF and Kenaf had be chosen to be analyzed because those natural fiber having high tensile strength compared to other natural fiber. So as the project is to build a drone, there had been an idea of developing the frame kit natural fiber like the PALF and the Kenaf material. In conclusion, each and every design having their own uniqueness where the best design with least stress was the design with circular shape.

The dependence on Unmanned Aerial Vehicles (UAVs) has greatly increased in many sectors around the globe. UAVs are in high demand and their technology is developing quickly, due to their ability to handle a variety of issues in a sophisticated manner. UAVs deployment in the aviation industry is still in the trial phase, thus certain adjustments must be made to make sure the UAVs meet safety standards. Safety is the most important factor in the aviation sector since it involves people’s lives. UAVs are required to make the maintenance of an aircraft more efficient. For instance, UAVs are capable of replacing the labor-intensive inspection procedure with conducive and safe regulation. Additional tools or sensors need to be added to the UAVs system to ensure the objective of applying UAVs is achieved. The camera mounted on the drone is able to enhance the functionality and widen the range of applications of UAVs. This thesis presents the UAV system that is able to assist during an aircraft inspection. The camera mounted on the drone is installed with an image processing program to identify the defect caused by a lightning strike.

Unmanned aerial vehicles (UAVs) have advanced and are now employed in a variety of industries, including aerial photography, the military, and transportation. Due to its low battery life, charging it can be difficult. A good UAV solution has been thought of as wireless charging. In this research, we suggested an inductively coupled wireless power transmission system (WPT) and examined the inductive coupling’s power efficiency. A portable energy receiving device positioned on the base of the UAV and a charging station with an induction coil array were both included in the WPT. Additionally, the WPT equivalent circuit was used to examine power efficiency, and a prototype model of the battery coupled with a quadcopter for testing power efficiency was developed. The results onboard the charging circuit design contributed with polarity modulation and safety charging the battery pack, with very light components that considerably decrease the size and weight as much as possible. The charging power conversion efficiency has achieved 83.76% at the maximum.

The development of hybrid composite materials using honeycomb structure, typically a lightweight material, is commonly used in aircraft structures. However, the use of honeycomb with natural or synthetic composite remains unexplored in the literature. Therefore, this study aims to partially replace synthetic fiber, woven glass with a natural fiber of woven kenaf and honeycomb core. An experimental analysis investigated the mechanical strength of three different compositions using glass, kenaf, and honeycomb materials for structural application purposes. The properties of the sample were evaluated through the tensile, flexural, and impact strength, and the morphological damage was observed using scanning electron microscopy. The results showed that the composition of GKGKG laminate composite is the highest in tensile strength (147.64 MPa) and modulus (3.9 GPa), while the GKHKG composite was good in flexural strength (219.03 MPa) and modulus (11.47 GPa). In terms of impact properties, there was a slight difference in energy level (20–30 J) by GKGKG and GKHKG, showing the optimal hybrid configuration of composite for the newly developed material. In conclusion, the application of the new hybrid of GKHKG composite is promising in semi-structural and structural light-weight applications.

In nondestructive testing (NDT), ensuring defect detection, measurement accuracy, and reliability guarantees various components' structural integrity and safety. The Probability of Detection (POD) concept has emerged as a fundamental measure of the effectiveness of an inspection technique in identifying defects. Since NDT plays a crucial role in aerospace, manufacturing, and infrastructure industries, enhancing POD has become critical. POD refers to the likelihood that a flaw or defect of a certain size will be detected using the NDT technique. The "â versus a" and the "hit/miss" methods are particularly notable among the commonly employed POD estimation methods. The POD curve is determined based on crack size measurements in the "â versus a" approach, typically used in ultrasonic testing. On the other hand, the "hit/miss" method establishes the POD curve by analysing binary outcomes, where a "hit" signifies successful detection and a "miss" denotes detection failure. This review focuses on POD in the context of NDT, specifically in phased array ultrasonic corrosion mapping (PAUCM), to uncover current uncertainty parameters and explore an innovative avenue for enhancing POD assessment by incorporating the material surface temperature as an additional parameter. [ABSTRACT FROM AUTHOR]

Cardiovascular disease remains the leading cause of morbidity and mortality globally, necessitating extensive research into the hemodynamics of blood flow under pathological conditions, such as atherosclerosis in carotid arteries. In vitro studies, particularly Computational Fluid Dynamics (CFD), are crucial for advancing our understanding of arterial blood flow and predicting pathological states. However, the accuracy of CFD simulations relies heavily on their validation against empirical data, such as those obtained from Particle Image Velocimetry (PIV). This study focuses on the comparative analysis of CFD predictions and PIV measurements of blood velocity vectors in a stented carotid artery bifurcation model under steady flow conditions derived from patient-specific data. The methodology involves simulating blood flow within a CFD framework and conducting PIV experiments using a blood-mimicking fluid seeded with particles in a carotid artery bifurcation phantom. The results indicate a reasonable agreement between the axial velocity vector profiles obtained via PIV and those predicted by CFD, with CFD predicting 10% higher than that recorded by PIV, especially in terms of recirculation areas and velocity values, despite some discrepancies in the velocity contours distribution, highlighting potential differences in how each method captures flow separation or recirculation areas. Despite some discrepancies in velocity contour distribution, which highlight potential differences in capturing flow separation or recirculation areas, the findings confirm that CFD simulations can effectively replicate the hemodynamics observed in carotid arteries and potentially other arterial segments. This study emphasizes the importance of integrating CFD simulations with experimental PIV data to validate and refine our understanding of arterial flow dynamics, significantly contributing to cardiovascular research and the development of interventions for arterial diseases. [ABSTRACT FROM AUTHOR]

Advances in today's technology have led to the use of composite materials with their advantages of significant high strength with lightweight structure in aircraft design worldwide. With the aid of simulation, ANSYS, two main common problems in designing the aircraft composite wing, which is the aerodynamic loading on the wing and composite modeling; whereby both can be coupled to solve the aforementioned problems. The paper addresses with the use of fluid Structure Interaction (FSI) simulation and developed a standard numerical approach by integrating the aerodynamic loading from fluid domain with Finite Element (FE) analysis from structural domain in the application of hybrid composite laminates of aircraft wing structure. In this study, the Computational Fluid Dynamics (CFD) is conducted on the selected wing model of Selig 1223 in order to obtain the pressure loading from fluid domain before transferring it as an input to FE composite of structural domain. The FSI simulation was performed for two parametric conditions, namely Composite Wing Skin without Honeycomb (CWS) and Composite Wing skin with Honeycomb (CWSwH). From the result, CWSwH has lower total deformation with 3.06% percentage difference compared to CWS. However, the shear stress and strain values of CWSwH showed higher value than those of CWS due to the effect of the elasticity of honeycomb core. Therefore, the numerical approach of FSI with the application composite material has proven to be feasible and significant of current research on the behavior of fluid flow and structural for the wing skin, which replicates the real conditions of the aircraft wing during take-off or cruise. [ABSTRACT FROM AUTHOR]

Background: The non-physiological structure of mechanical heart valves (MHVs) affects the blood flow field, especially the complex microstructure at the hinge. Numerous studies suggest that the blood flow field in the aortic area with an MHV can be considered Newtonian. However, the Newtonian assumption is occasionally unreasonable, where blood viscosity changes with shear rate, exhibiting non-Newtonian shear-thinning characteristics. Methods: In this research, a comprehensive study of the non-Newtonian effects on the hemodynamic behavior of MHVs was performed. The impact of the Newtonian hypothesis was investigated on the internal hemodynamics of MHVs. Several non-Newtonian and Newtonian models were used to analyze the chamber flow and blood viscosity. MHVs were modeled and placed in simplified arteries. After the unstructured mesh was generated, a simulation was performed in OpenFOAM to analyze its hemodynamic parameters. Results: In the study of the non-Newtonian viscosity model, the Casson model differs significantly from the Newtonian model, resulting in a 70.34% higher wall shear stress. In the modified Cross and Carreau models, the non-Newtonian behavior can significantly simulate blood in the MHV at different stages during initial and intermediate deceleration. The narrowing of the hinge region in particular, has a significant impact on evaluating blood rheology. The low flow rate and high wall shear force at the hinge can cause blood cell accumulation and injury time, resulting in hemolytic thrombosis. Conclusion: The results exhibit that the Newtonian hypothesis underestimates the hemodynamics of MHVs, whose complex structure leads to increased recirculation, stagnation, and eddy current structure, and a reasonable choice of blood viscosity model may improve the result accuracy. Modfied Cross and Carreau viscosity models effectively exhibit the shear-thinning behavior in MHV blood simulations. [ABSTRACT FROM AUTHOR]

Coconut shell is an agricultural residue, usually disposed of through open burning. Toxic gases have been emitted from the open burning phase and can therefore be detrimental to human health and the environment. Thus, to reduce the risk of pollution, researchers have developed a new technology by using agro-wastes to produce biocomposites. Coconut shell powder (CSP) is a solid nonfood waste, which can be potentially exploited to reduce the usage of synthetic fiber. Coconut shell is also low-cost and low weight material that can be used to reduce the production cost of and fuel consumption for transportation. This review has focused on the research carried out on the CSP loaded into different types of matrices, highlighting the fundamental, mechanical, physical, and thermal properties of CSP composites. This article also provides critical review of the development for CSP composite and the summary of the results presented in the literature, focusing in the properties of CSP with polymeric matrices and the application design for economical products. [ABSTRACT FROM AUTHOR]