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This paper deals with the application of 1-D simulation technique for prediction of engine performance at high altitudes. 1-D engine simulation is an important tool for engine development activities. Engine design through simulation can substantially cut down time needed to execute experiments and prototyping, as todays softwares can simulate most of the experiments. This approach was applied for simulation of a spark-ignited engine for UAV. A detailed 1-D thermodynamic model was prepared for the engine configuration in Ricardo WAVE environment; different simulation runs were executed and then performance parameters like brake power, torque, specific fuel consumption, BMEP, in-cylinder pressure etc. were predicted. In 1-D simulation technique, predicted performance shall always be co-related with test results for correct interpretation.

The non-contact overload recognition method refers to the method of detecting the vibration state of the vehicle through visual recognition without touching the vehicle, and then calculating the vehicle load in combination with the vehicle dynamics model to determine whether the passing vehicle is overloaded. Due to the convenience of detection, low cost of infrastructure and informatization, this method has great advantages in the field of overload identification. However, the model used in this recognition method is the single mass vibration model at present, which will have a large error due to the interaction between the front and rear suspension, and the position of the center of mass needs to be acquired in the recognition process, which is difficult in the actual identification process. In this paper, a vehicle vibration model containing two modes of vibration is proposed, and uses Sobol algorithm to analyze the parameter sensitivity of the model.

Having connectivity among ground vehicles brings about benefits in fuel economy improvement, traffic mobility enhancement and undesired emission reductions. On the other hand, Unmanned Aerial Vehicles (UAV) have proven to help in getting aerial data to end users in an affordable manner. When UAVs are equipped with cameras, they can get information about the terrain they are flying over. Moreover, using Vehicle-to-Everything (V2X) communication technologies, it is possible to form a communication link between UAVs and the connected ground vehicle networks comprising of Connected and Autonomous vehicles (CAVs). To investigate and exploit the potential benefits and use cases of a broad vehicle network, a microscopic traffic simulator modified previously by our group with the addition of nearby UAVs is used to integrate simulated Connected UAVs flying above a realistic simulation of heterogeneous traffic flow containing both CAVs and non-CAVs.

Automotive digital cockpit is growing multi-dimensionally through multiple numbers of applications for driver assistance and user activities. The exponential growth of diverse applications provides global connectivity to the vehicles, but it equally provides a passage for the global security threats to reach the automotive surface by increasing the attack surfaces on the vehicles. The controlled interaction of the vehicular applications with the external digital world protects vehicular confidentiality and integrity, where the violation of which affects the automotive safety and security. The controlled interaction of the applications is achieved through a firewall system either to pass or block traffic through the networking interface. The opening and closing of ports using static and dynamic firewall suffer from their own shortcomings, where those instances provide open ports for the attackers to launch the attacks by accessing the ports.

Every state-of-art aircraft has a complex distributed systems of avionics Line Replaceable Units/Modules (LRUs/LRMs), networked by several Data buses. These LRUs are becoming more complex because of an increasing number of new functions need to be integrated into avionics architecture. Moreover, the complexity of the overall avionics architecture and its impact on cable length, weight, power consumption, reliability and maintainability of avionics systems encouraged manufacturers to incorporate efficient avionics architectures in their aircraft design process. The evolution of avionics data buses and architectures have moved from distributed analog and federated architecture to digital integrated modular avionics (IMA). IMA architecture allows suppliers to develop their own LRUs/LRMs capable of specific features that can then be offered to Original Equipment Manufacturers (OEMs) as Commercial-Off-The-Shelf (COTS) products.

Relationships develop between people. In their infancy they are cautious and experimental, but upon maturation they become trusting and reliable. Businesses are interested in hastening this process, as commerce is also an event occurring between people, and 2 parties that trust the goods or services of each other welcome a free exchange agreement. This transfer is not limited to the tangible but also encompasses idea- and knowledge-sharing within an organization, the ability to make quality decisions, and action-oriented collaboration. With the global expansion of organizations, the reality of remote teams, and an increasing desire among talent to operate on a flexible schedule, establishing functioning teams that flourish has become ever more challenging. Reframing the issue into a relationship and trust development challenge allows organizations to introduce conferencing tools such as live video streaming during remote conferencing as a solution to maintaining a meeting community.

A new numerical approach is proposed for studying possible vibrations caused by drilling during the assembly of aircraft structures. It is based on modelling of the stress-strain state of assembled structures by solving the corresponding transient contact problem. This approach is intended for fast dynamic analysis of the structure in the drilling area. It includes a time discretization algorithm, a special reduction technique and a reformulation of contact problem in terms of quadratic programming. The high speed of the algorithm allows one to combine the non-stationary calculations with variation analysis in order to check the possible deviations in the shape of assembled parts. The proposed approach is validated by commercial software and it is also applied for analysis of a test problem.

As commercial transport aircraft progress toward a future More Electric Airplane (MEA) there are numerous opportunities to improve energy management of the electrical power system. Improved energy management of the airplane electrical power system not only has the potential to decrease the weight and improve the efficiency of the system, but also to improve system stability and reliability. This paper analyzes re-architecting of an MEA airplane electrical power system in order to better manage the current electrical loads. It also considers the use of new sources of power generation and energy storage that would enable improved energy management for a new improved MEA such as fuel cells, batteries and super capacitors.

Unmanned Aerial Vehicles (UAVs) are becoming an effective way to serve humanitarian relief efforts during environmental disasters. The process of designing such UAVs poses challenges in optimizing design variables such as maneuverability, payload capacity and maximizing endurance because the designing of a BWB takes into account the interdependency between the stability and aerodynamic performance. The Blended Wing Body is an unconventional aircraft configuration which offers enhanced performance over conventional UAVs. In this study the designing of a BWB is investigated with an aim to achieve structurally sound and aerodynamically stable configuration. The design has been done by taking into consideration the side and top view airfoil for fuselage, because fuselage is a major lift generating portion in the UAV. For designing the control surfaces, the two major requirements for a controlled and safe flight of a UAV are its stability and maneuverability.

The quest for achieving more efficient gas turbine engine systems (GTESs) has led the researchers to try getting into many new dimensions of research. Simple Brayton cycle-based GTESs were coupled with recuperators, regenerators and reheaters to avoid/recoup heat energy from being wasted and these were designated as complex GTESs. Multistage compression (multi-casing) in axial compressors and multistage (two-cylinder) expansions in turbines paved the path to optimize the plant design for greater thrust to weight ratio and greater efficiency of the GTESs. Since the increase in efficiency of any power plant is directly or indirectly related to temperatures at which the plant cycle is being operated, this thermodynamic constraint had led to the development of high temperature materials such as single crystal nickel-based superalloys.

Commercial transport airplane technology is moving toward a next generation More Electric Airplane (MEA) in order to further improve airplane performance and efficiency. Electricity is seeing increased use for power generation, transmission and energy storage in place of less efficient pneumatics and hydraulics. The MEA is also a technology enabler for new environmentally friendly electrical generation and storage devices such as fuel cells, batteries and super capacitors. Successful use of these new technologies requires systematically analyzing the interface of these technologies with each other, and with other systems that impact overall airplane performance, efficiency, weight and reliability. In this paper, incremental changes in the airplane power system will be analyzed. With each of these changes, the benefits to the electrical power system and the impact that each change has on the airplane will be estimated.

In racing applications, the constant search for improvement has been changing new projects’ development approach. The time available for designing has become smaller, while requirements on performance improvement continuously persist in the daily routine of competition engineering. Since suspension systems play a big role in vehicle dynamics, affecting directly the tire performance of the vehicle under design, hence, the overall performance of the car on the track, computational methods are proven to be a crucial tool for developing new prototypes and making decisions. Under this point of view, optimization techniques have exploited new computational resources, which are constantly getting cheaper, to search for new engineering solutions. This work presents the methodology used and the results obtained from the kinematics optimization of a Formula Student suspension system through the application of heuristics method techniques.

Reduction gears are very commonly used in the automotive and aviation industries. A propeller’s efficiency decreases rapidly as the speed of the blade tips nears the speed of sound. An engine reduction gear enables the engine to develop more torque while reducing the propeller’s revolutions per minute (RPM). This prevents the propeller’s efficiency from decreasing. This work deals with a detailed methodology for the design and analysis of a single-stage reduction gear. Custom pinion and wheel were modelled along with the engine assembly. A custom mount was designed and fabricated to allow for engine-reduction gear system integration. In this work, a 7.5 cubic centimeter (cc) single-cylinder glow engine is used. Bending and contact stress analysis was performed, and the results were compared with the calculated stress values. The torque demands were analyzed for propellers of different sizes at varying aircraft speeds.

The major emphasis in Fault-Tolerant Flight Control (FTFC) System is towards Fault Detection and Diagnosis (FDD). FDD is used to isolate the aircraft’s fault and provides information for reconfiguration mechanisms to recover the system from a faulty state. In this paper, based on the classification of faults in actuators and sensors, FTFC system design methods are proposed while retaining the existing flight control system (FCS) architecture. Fault scenarios broadly can be classified as one that can be identified and addressed using a sensor or actuator redundancy management (RM) algorithm and the other that need to be identified using real-time system identification techniques. The reconfiguration carried out for the former is termed as passive FTFC, whereas the latter as active FTFC.

Vehicle aerodynamic drag reduction is the effective technique to enhance the fuel economy, performance and top speed of a vehicle. Out of the total drag, the underbody drag contributes about 40-50% by the parts like wheel arch, wheel housing, and the wheels. This further increases in the case of vehicles with higher CG. Thus, it seems logical to focus attention on the underbody aerodynamic drag reduction. In this study, an active spoiler is placed towards the front end of the vehicle which will divert the air flow from the front towards the radiator. The active spoiler revolves according to the signals received from the radar sensors placed at the lower end to detect obstacles which will prevent it from damage. The aim of the study is to examine the effect of the air flow diversion on underbody drag. The effect of air flow diversion on fuel consumption, radiator effectiveness and top speed is numerically evaluated.

The International Space Station's primary external heat transport system is a single phase ammonia loop called the Active Thermal Control System (ATCS). ATCS loop heat is acquired from the station modules through interface heat exchangers (Internal Thermal Control System water to ATCS ammonia) and from external truss mounted electronics through cold plates. The heat exchangers are compact plate/fin counterflow type and the cold plates are a brazed and bonded construction using a radiation heat transfer interface to the electronics.

Sales of SUV and luxury cars on the largest market of the world - China - are growing at a high rate. The highways in large cities like Beijing or Shanghai are increasingly populated with cars from all over the world like Japan, USA, Europe and Korea and even some refined domestic brands. More than 10 million rich people can afford those cars and are skilled drivers. This huge group of potential consumers is targeted by luxury brand OEMs and by startup companies. It has been understood that these people have a high expectation of comfort. The twistbeam rear axle was replaced by multilink, double clutch transmissions were improved by comfort-mode drive programs, interior trims raised to Western standard performance levels, tyres specially developed for comfort in China, localized insulation materials and packages engineered to a one vehicle class higher level.

An integrated circuit has been designed for use as a single supply, MIL-STD-1553 transceiver using BiCMOS technology. Use of the BiCMOS fabrication process has advantages over both Bipolar and CMOS technologies. These advantages include: reduced standby current drain, increased flexibility in mating the transceiver to various remote terminals, increased control over output amplitude and rise/fall times, easier methods for adjusting filter response and residual voltage, and reduced chip size (over a CMOS transceiver). Development of this monolithic transceiver opens the door to future advances in remote terminal design. By combining the current driving capacity of Bipolar with the digital design capability of CMOS, the next probable step in the progression of MIL-STD-1553 technology would be a fully monolithic remote terminal. This device would combine a transceiver with the encoder/decoder and protocol logic on a single semiconductor device.

Extremely uncomfortable levels of bounce and pitch vibrations are produced when a CV moves over uneven terrain. The present study was carried out to ascertain the vibrational response at the driver’s, commander’s and trooper’s seats. A 23 -degrees of freedom (DOF) lumped parameter 3-D model of a combined CV and human body was made. The vehicle had 15 DOF corresponding to the bounce, pitch and roll of the hull (sprung mass) and bounce motions of the 12 wheel stations (unsprung masses) on either side. The human body was idealized as having 8 DOF corresponding to bounce motions of the pelvis, abdomen, diaphragm, thorax, torso, back and head. The seat was also assigned a bounce DOF. The lumped masses of the body parts were distributed and connected by springs. The differential equations of motion for the linear rigid body model were formulated and the natural frequencies of different parts of the human body and the military tank were determined by eigenvalue analysis using MATLAB.

Additive manufacturing (AM) technology, also known as 3D printing, has transitioned from concepts and prototypes to part-for-part substitution and the creation of unique AM-specific part geometries. These applications are increasingly present in demanding, mission-critical fields such as medicine and aerospace, which require materials with certain thermal, stiffness, corrosion, and static loading properties. To advance in these arenas, metallic, ceramic, and polymer composite AM parts need to be free from discontinuities. The manufacturing processes have to be stable, robust, and repeatable. And the nondestructive testing (NDT) technology and inspection methods will need to be sufficiently capable and reliable to ensure that discontinuities will be detected to prevent the components from being accepted for use. As the second installment of a six-part series of SAE EDGE™ Research Reports on AM, this one discusses the need, challenges, technologies, and opportunities for NDT in AM.