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    Cover Page Volume 74, Issue 1 (2024)

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    RAZOR A Lightweight Block Cipher for Security in IoT

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    Rapid technological developments prompted a need to do everything from anywhere and that is growing due to modern lifestyle. The Internet of Things (IoT) technology is helping to provide the solutions by inter-connecting the smart devices. Lightweight block ciphers are deployed to enable the security in such devices. In this paper, a new lightweight block cipher RAZOR is proposed that is based on a hybrid design technique. The round function of RAZOR is designed by mixing the Feistel and substitution permutation network techniques. The rotation and XOR based diffusion function is applied on 32-bit input with 8 branches and branch number 7 to optimize the security. The strength of RAZOR is proved against differential, linear, and impossible differential attacks. The number of active S-boxes in any 5-round differential characteristic of RAZOR is 21 in comparison to the 10, 6, 4, 7, and 6 for PRESENT, Rectangle, LBlock, GIFT, and SCENERY respectively. RAZOR provides better security than the existing lightweight designs. The average throughput of 1.47 mega bytes per second to encrypt the large files makes it a better choice for software oriented IoT applications

    Fault Tolerant Brushless DC Motor Drive for Aerospace Applications

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    This article brings out a Fault-tolerant BLDC motor drive for aerospace applications using the redundancy concept. In a way, it brings out a fault-tolerant strategy that can be used to continue the regular operation of a BLDC motor drive even after the occurrence of faults. As BLDC motors are used in critical and dangerous control areas like military services and space vehicles, a fault-tolerant drive is essential to maintain drive operation and provide desirable output. This article compares fault simulation results in the software model of a BLDC motor drive to those of fault simulation results in hardware for three main types of faults. Fault simulation is carried out for three types of faults, viz. inverter device open circuit fault, motor winding open circuit fault, and rotor position sensor (hall sensor) open-circuited fault. Fault tolerance is ensured by introducing a redundant drive (drive-2), which operates the complete drive at the advent of any of the faults mentioned above in the main (healthy) drive-1. A fault-tolerant (redundant) hardware comprising dual stator BLDC motor and redundant controllers is realized and operationalized. Fault simulation is carried out in this hardware, and these results are validated with the results of fault simulation in the MATLAB SIMULINK model. Software and hardware results are comparable and form a basis for developing fault-tolerant electro-mechanical actuation systems for high-reliability, high-cost applications, mainly aerospace

    Analysis of Pilot Distance Estimation in Different Lighting and Visibility Conditions

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    Several studies on distance and size estimation have focused on normal and night vision goggles (NVGs), but none of them have been performed during the twilight period. Hence, in this study, distance was estimated for the first time during nautical twilight. According to the findings, the accuracy of distance estimation reduces as visibility decreases and is restricted. When compared with Day Limited Helmet Mounted Display Vision (M = 5.27, SD = .59), Twilight Normal Vision (M = 5.33, SD = .69) and Twilight Helmet Mounted Display Vision (M = 5.20, SD = .61), NVG (M = 4.79, SD = .57) appears to have a lower error rate. In this study, distance was estimated considering objects determined during the helicopter flight by the pilots in different visibility conditions, which are significant in the field of aviation. This work is unique owing to its coverage of helicopter pilots and the estimation during the twilight period. In view of our findings, it may be reasonable to postpone the planned helicopter flights during poor visibility conditions

    Process Optimization and Design of an Automation Controller for a Multidisciplinary Combat Engineering System

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    Design of an automation controller for a “Electro-Hydro-Mechanical Object Laying System” is presented in this paper, which is a multidisciplinary equipment consisting of Electromechanical and Hydraulic Actuators and large number of sensors for process feedback. There are complex mechanisms and processes involved in this system, which are required to be operated/executed in sequential and parallel manner in real time. The operation of spatially distributed Electromechanical & Hydraulic actuators with feedbacks from multiple type of sensors are required to be synchronized for multiple activities at a faster rate along with safely handling of the objects. All the activities are automated with minimum human intervention to avoid risk to the crew. This paper mainly focuses on electronic controller hardware design for military environment and process optimization to achieve faster object laying rate

    Aerodynamic Investigation of Blended Wing Body Configuration

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      A blended wing body (BWB) configuration is an unconventional aircraft design in which the wing and fuselage are blended to form an aircraft. This design concept has inherent higher aerodynamic efficiency, environmental benefits and capacities. These advantages make the BWB configuration a feasible concept for commercial transport aircraft. In the present work, a 3-D BWB model is designed in SolidWorks and fabricated using a 3D printer. The numerical and experimental analyses are carried out with this BWB geometry. Aerodynamic characteristics and flow features obtained from the open-source CFD software OpenFOAM have been studied, analyzed, and compared with the wind tunnel results. Experimental and computational data compare well and the present BWB can operate at a high angle of attack. The coefficient of lift (CL) increases with AoA up to 45º. The CL starts decreasing beyond this AoA, and the present BWB geometry stalls at around AoA = 45º. The coefficient of drag (CD) increases with the increase in AoA due to the spreading of the separated region over the geometry. Lift/Drag (L/D) variation with AoA is also studied to find the optimum flight configuration of the present BWB geometry. Sectional pressure distribution at different spanwise locations, velocity contours, pathlines, surface limiting streamlines and tuft flow visualization are also presented to investigate the flow. The studies investigate the aerodynamics, flow field and optimal flight configuration for cruising a BWB geometry

    A Theoretical Approach in the Design of Single Frame 28 V DC and 270 V DC Dual Voltage Generator

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    Armored Fighting Vehicles (AFVs) generally operate with a 28 V DC electrical system. However, the demand for electrical power in AFVs has exceeded the capabilities of the existing 28V system. The additional load growth necessitates larger wire sizes, which adds extra weight and cost to the vehicle. Introducing a dual-bus architecture (28 V DC and 270 V DC) can lead to the efficient operation of the electrical system while meeting future demand. This paper presents the design of a Brushless Direct Current (BLDC) Dual Voltage Generator (DVG), which simultaneously outputs two voltages (28 V DC & 270 V DC) from a single frame across a wide operational speed range. The design process includes a detailed description of the individual stages, accompanied by analytical parameters and software-generated results. The modeling and analysis of the generator were carried out using Motorsolve design software. The obtained results are presented and thoroughly discussed in this paper

    Experimental Investigation and Thermophysics Analysis of Joule Thomson Cooler Applicable to Infrared Imaging

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    Recuperative type of heat exchanger (H-E) based miniature Joule-Thomson (J-T) cooler operated in the steady-state condition is employed extensively in applications towards infrared detectors cooling, thermal imaging cameras, and homing guidance devices in a wide variety of defence projectile systems. In this study, a theoretical thermal design of recuperative H-E for determining a viable geometry using iterative methodology is discussed. A steady-state numerical analysis for the developed geometrical model of the H-E is also reported, along with the experimental studies for typical operating conditions. A custom numerical code using the Runge-Kutta method has been developed in MATLAB, and the results from the code compared with predictions of COMSOL multi-physics are in good agreement. Further, results have been validated proving the efficacy of the theoretical model and custom numerical code developed

    Human Error Management in Aviation Maintenance using Hybrid FMEA with a Novel Fuzzy Approach

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    Human errors significantly contribute to aviation accidents during aircraft maintenance. Therefore, managing human errors becomes a critical aspect of aviation maintenance. The existing literature has extensively analysed human errors. However, there is a gap in accurately identifying and prioritising critical human errors and effectively managing them to reduce incidents and accidents. This research work proposes a novel fuzzy approach for human error analysis using a hybrid FMEA with Fuzzy AHP-TOPSIS. We identified inadequate maintenance processes, attention/memory, inadequate documentation, inadequate supervision, judgement/decision-making, and knowledge/rule base as some of the critical human errors in aircraft maintenance. Based on these findings, we recommended practically implementable solutions at the organisational, workspace, and individual levels to mitigate human errors in aircraft maintenance

    Technological Perspectives of Countering UAV Swarms

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    Conventional AD systems have been found less effective for countering UAVs and loitering munitions. Thishas necessitated the development of counter-UAV systems with different functionalities. A cluster of armed UAVsas swarm formations has further rendered the conventional AD systems far from effective, emphasizing the need to consider countering swarms as the most crucial element in new-generation aerial threat mitigation strategies. In this paper, the capabilities of UAV swarms and vital military assets exposed to such attacks are identified. To protect the vital assets from aerial swarm threats, ideal system characteristics of a counter-UAV (C-UAV) swarm system to overcome the challenges are discussed. Currently available acquisition & engagement technology is analyzed and the application of these systems to counter swarm applications is brought out. New requirements are discussed and a conceptual design of a layered system is derived which can handle a large spectrum of aerial threats including a swarm of UAVs. This system is expected to have a higher rate of engagement and can be designed with low-cost network-integrated systems

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