In the recent past small-scale Unmanned Aerial Vehicles (or Unmanned Aerial System as it is called presently) have evolved as an important tool in non-conventional fields like agriculture, e-Commerce, policing, medical logistics in addition to military applications [11]. This paper presents the complete methodology (very limited article exists)applied to optimally design the wing of a small scale Unmanned Aerial Vehicle with help of widely used CFD software, ANSYS to maximize its efficiency. In this study, the application of computational methods in the iterative design process is successfully explored. The various design parameters and features of wing also have been explored with help of CFD analysis to derive the advantages. The strength and stiffness analysis of the UAV wing has also been carried out using ANSYS. The modelling of wing and associated parts were carried out on CATIA. The final design of the wing has two spars, 20 ribs a side with mid wing root strengthening, near elliptical plan form and has an all composite structure. The wing is lighter in weight as compared to a similar wing made from Aluminum view weight optimization, and strong enough to meet all inflight load conditions with safety margins. This paper demonstrates the design process/methodology to optimally design an efficient small-scale UAV.

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The interest in dynamic behavior of railway bridges has increased in recent years with the introduction of high speed trains. Higher speeds of the trains have resulted in larger and more complicated loads than earlier, producing significant dynamic effects. The dynamic aspects are of special interest and have often shown to be the governing factor in the structural design. Dynamic analysis of railway bridges is, therefore, required for high train speeds. The objective of this paper is to investigate the dynamic behavior of an existing railway bridge subjected to high speed trains. A railway bridge model has been developed to study dynamic effects such as oscillations produced by moving loads of constant magnitude and to obtain a relation between the velocity, acceleration, load position and deflection of the bridge at any instant of loading, with and without damping, with the help of MATLAB software. The simulation results indicate that the speed of the vehicle is a very important parameter influencing the dynamic response of a railway bridge. The amplitude of bridge deflection has been found to be the highest at speeds between 75 and 85 m/s. Further, the introduction of damping has been found to greatly influence of the amplitude of bridge deflection response. However, the peak deflection values appear at the same speed independent of the damping coefficients.

A warship may be detected in hostile waters because of its unique acoustic signature. A typical two-stage passive vibration isolation system used on ships and submarines to isolate onboard machinery is the floating raft isolation system. The passive isolation system, though robust, may result in substantially high transmission of forces to the foundation at certain excitation frequencies, adversely affecting the ship's stealth. This paper highlights the results of a simulation study aimed at the design of a semi-active floating raft vibration isolation system with the objective of mitigating the acoustic signature of a warship by minimising the transmission of forces, resulting from operation of onboard machinery, to the foundation. A semi-active control scheme with variable damping has been proposed for the floating raft, the variable damping being achieved by means of an electrorheological (ER) damper. A fuzzy logic controller has been designed to achieve the best isolation effect by analysing the characteristics of the frequencies in the excitation signal. The designed semi-active control system is subjected to a time-varying signal, each time-segment corresponding to a different optimal damping ratio. The MATLAB simulation results indicate that the proposed fuzzy logic control method is more effective in vibration isolation than the passive method thereby indicating the potential of the designed semi-active control system in reducing a ship's acoustic signature.

Gearboxes are employed in a wide variety of applications, ranging from small domestic appliances to the rather gigantic power plants and marine propulsion systems. Gearbox failure may not only result in significant financial losses resulting from downtime of machinery but may also place human life at risk. Gearbox failure in transmission systems of warships and single engine aircraft, beside other military applications, is unacceptable. The criticality of the gearbox in rotary machines has resulted in enormous effort on the part of researchers to develop new and efficient methods of diagnosing faults in gearboxes so that timely rectification can be undertaken before catastrophic failure occurs. Artificial intelligence (AI) has been a significant milestone in automated gearbox fault diagnosis (GFD). This chapter reviews over a decade of research efforts on fault diagnosis of gearboxes with AI techniques. Some of areas of AI in GFD which still merit attention have been identified and discussed at the end of the chapter.