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Rotordynamics developed from the beginning of the 20th century to deal with problems associated with steam turbines. This paper deals with intense developments starting around 1975 through 2000 in rotordynamics to deal with new, larger machines running at higher speeds and higher power levels. Most of the new problems of interest dealt with subsynchronous instabilities. Issues associated with “synchromnously unstable” motion due to the Morton Effect is also reviewed.

Traditional User/Maintenance Manuals provide useful information when dealing with simple machines. However, when dealing with complex systems of systems and highly miniaturized technologies, like UAVs, or with machines with millions of parts, a commercial aircraft is a case in point, new technologies taking advantage of Augmented Reality can rapidly and effectively support the maintenance operations. This paper presents a User/Maintenance Manual based on Augmented Reality to help the operator in the detection of parts and in the sequence to be followed to assemble/disassemble systems and subsystems. The proposed system includes a handheld device and/or an head mounted display or special goggles, to be used by on-site operators, with software management providing data fusion and overlaying traditional 2D user/maintenance manual information with an augmented reality software and appropriate interface.

In many parts of the world, uncontrolled fires in sparsely populated areas are a major concern as they can quickly grow into large and destructive conflagrations in short time spans. Detecting these fires has traditionally been a job for trained humans on the ground, or in the air. In many cases, these manned solutions are simply not able to survey the amount of area necessary to maintain sufficient vigilance and coverage. This paper investigates the use of unmanned aerial systems (UAS) for automated wildfire detection. The proposed system uses low-cost, consumer-grade electronics and sensors combined with various airframes to create a system suitable for automatic detection of wildfires. The system employs automatic image processing techniques to analyze captured images and autonomously detect fire-related features such as fire lines, burnt regions, and flammable material.

The maturity reached in the development of Unmanned Air Vehicles (UAVs) systems is making them more and more attractive for a vast number of civil missions. Clearly, the introduction of UAVs in the civil airspace requiring practical and effective regulation is one of the most critical issues being currently discussed. As several civil air authorities report in their regulations “Sense and Avoid” or “Detect and Avoid” capabilities are critical to the successful integration of UAV into the civil airspace. One possible approach to achieve this capability, specifically for operations beyond the Line-of-Sight, would be to equip air vehicles with a vision-based system using cameras to monitor the surrounding air space and to classify other air vehicles flying in close proximity. This paper presents an image-based application for the supervised classification of air vehicles.

SUAV is a 4 year investigation with the aim of designing, manufacturing and integrating a 3kg Solid Oxide Fuel Cell (SOFC) into an existing 11kg fixed wing UAV which is already in commercial service. The project comprises of a collaboration of ten partners, each having a commercial or scientific interest in the design. Individual partners provide specific specialist knowledge at system component level. This paper will present an overview of the problem space and show the methods used to generate the system level requirements. A top level overview of the resultant system design is also given.

The innovative highly flexible wings made of extremely light structures, yet still capable of carrying a considerable amount of non- structural weights, requires significant effort in structural simulations. The complexity involved in such design demands for simplified mathematical tools based on appropriate nonlinear structural schemes combined with reduced order models capable of predicting accurately their aero-structural behaviour. The model presented in this paper is based on a consistent nonlinear beam-wise scheme, capable of simulating the unconventional aeroelastic behaviour of flexible composite wings. The partial differential equations describing the wing dynamics are expanded up to the third order and can be used to explore the effect of static deflection imposed by external trim, the effect of gust loads and the one of nonlinear aerodynamic stall.

The problem of wing shape modification under loads in order to enhance the aircraft performance and control is continuously improving by researchers. This requirement is in contrast to the airworthiness regulations that constraint stiffness and stress of the structure in order to maintain structural integrity under operative flight conditions. The lifting surface modification is more stringent in those cases, such as UAV configurations, where the installed power is limited but the variety of operative scenario is wider than in conventional aircraft. A possible solution for adaptive wing configuration can be found in the VENTURAS Project idea. The VENTURAS Project is a funded project with the aim of improve the wind turbine efficiency by means of introducing a twisting capability for the blade sections according to the best situation in any wind condition. The blade structure is composed by two parts: 1) internal supporting element, 2) external deformable envelope.

Automatic Dependent Surveillance Broadcast (ADS-B) [1] is a technology that can be viewed either as a complement or as an alternative to current radar-based surveillance techniques. Despite its many benefits, this technology suffers from the security flaw of having its messages sent as clear text broadcasts, which makes it vulnerable to several kinds of attacks affecting the authenticity and integrity of ADS-b messages - a problem we addressed with a security framework presented in previous work [2]. In this paper, we propose to enhance that initial work by using keyed-hash message authentication code [3] (HMAC) to ensure the authenticity and integrity of ADS-B messages. The proposed improvements include changing the structure of the security-related data and, more importantly, adding a cognitive risk adaptive module. These improvements resulted in four main contributions. First, the new structure of the security-related data is more resilient to messages being lost or scrambled.

VPX, as a switched fabric, supports the design of advanced integrated systems using technologies such as deterministic Ethernet. Deterministic Ethernet can be used in backplane and backbone applications. In cases where functional interrelationships and Ethernet network bandwidth sharing is deterministic and all logical links among critical function have configurable quality of service with guaranteed timing, the complexity challenges in design of advanced integrated architectures can be much simpler to handle and mitigate. VPX switches in 3/6U format with ARINC664 and SAE AS6802 services enable deterministic integration of many critical functions hosted on common embedded computing and networking resources. Both ARINC664 (asynchronous real-time) and SAE AS6802 (synchronous hard real-time), as Layer 2 enhancements, do not affect existing Ethernet services.

The joining and assembly of barrel sections of large aircraft is always cumbersome. Any means to ease this task are welcome. In recent years The Boeing Co. has invented and licensed their “Flex-Track” system. But however flexible this approach may be, double curved surfaces, large variations of cross-section radius and issues with vacuum cup fixture are problems to be dealt with. Zhejiang University in Hangzhou, China has developed a new, innovative circumferential splicing system in cooperation with Broetje-Automation, Germany. There is a unique, time-saving setup technology and self-stepping actuation for a one up 360° splicing operation. The process endeffector is based on standard, state of the art components in use for large fastening systems. Features are high speed servo drilling spindle with HSK 32 drill chuck holder, tool changer, vacuum chip removal, reference hole detection and correction, surface normality alignment, pressure foot clamp-up, countersink control.

This paper presents an innovative solution of portable drilling machine, lightweight and low cost, dedicated to drilling operations on single and double curved aircraft structure. Aircraft Standard drilling process mainly uses drilling templates combined with Automated Drilling Units (ADU) which is a very efficient solution. However, the management of templates and ADUs is a time consuming and costly task in regards to the large quantity of existing references spread over every aircraft production sites. Therefore, to help reducing those costs and also workload, the concept of the Numerical Template (NCT) has been designed, using classic and robust mechanical devices, hand-held, lightweight and universal. NCT architecture concept could led to a family of NCT with different dimensions of frame parts(X,Y,Z), fitted to the targeted area geometry. The system is able to guaranty an accuracy of ± 0.5 mm and a normality of ±0.5°.

In the aircraft design process there are the occasional bolted joints with opposing surfaces that are not parallel to each other. This can necessitate manufacturing to machine a spot face into the structural surfaces for the bolt head and nut to seat on. Typically this process is done manually by two workers with all process verification being done visually. Additionally, the nature of airplane structure often requires one worker to be inside a confined space to monitor the process. With this in mind, a tool was requested to reduce the number of workers required, remove workers from confined spaces and ensure a robust method for process validation. The critical technology that would have to be developed was a device that could fix itself into an existing hole, measure the surface of which the hole exited and then machine a spot face into that surface to a specific calculated depth. The device would only require a single operator to install and start the machine in a given hole.

This paper presents test results of a 50 kW Organic Rankine Cycle (ORC) system and proposed guidelines for how to effectively apply this system to the rural Alaska power industry. In rural Alaska, approximately 180 villages rely on off-grid diesel generators for power. Most of the generators have capacities of about 1 MW or less. In general, the average operation efficiencies are noticeably less than 40%, with the rest of the fuel energy becoming heat. If the heat is not applied for useful application, it is called waste heat. Most of the wasted heat is contained in engine exhaust and jacket fluid and eventually dissipates into the environment. For rural Alaska, waste heat for heating is most effective; in many cases, waste heat for power may be needed due to a variety of reasons. Many rural Alaskan villages are reluctant to apply exhaust heat recovery due to concerns about corrosion and soot accumulation in the exhaust system and their effect on emissions.

Previous research on both small-scale and full-scale vehicles shows that base extensions are an effective method to increase the base pressure, enhancing pressure recovery and reducing the wake size. These extensions decrease drag at zero yaw, but show an even larger improvement at small yaw angles. In this paper, rear extensions are investigated on an SUV in the Volvo Cars Aerodynamic Wind Tunnel with focus on the wake flow and on the unsteady behavior of the surface pressures near the base perimeter. To increase the effect of the extensions on the wake flow, the investigated configurations have a closed upper- and lower grille (closed-cooling) and the underbody has been smoothed with additional panels. This paper aims to analyze differences in flow characteristics on the wake of an SUV at 0° and 2.5° yaw, caused by different sets of extensions attached to the base perimeter. Extensions with several lengths are investigated with and without a kick.

A smart way to reduce CO2 emission in transportation sector is to recover energy usually wasted and re-use it for engine and vehicle needs. ORC plant on exhaust gas of ICE is really interesting, but it has a significant impact on the exhaust line and vehicle's weight. The backpressure realized in the exhaust and the weight gain, in fact, produce a specific fuel consumption increase as well as an increase in the propulsion power: both terms could vanish the energy recovered. The paper discusses the effects of the pressure losses produced by an ORC plant mounted on the exhaust line of an IVECO F1C test bench engine. The interactions produced on the turbocharged engine have been experimentally investigated: the presence of an IGV turbocharger makes the effect of the backpressure not straightforward to be predicted and needed a full experimental testing of the group in order to understand its reaction and the net effect in terms of specific fuel consumption.

In Engine Management System, more accurate control is required to improve engine performance. Especially generating the precise ignition signal has a direct effect on better engine performance. In the beginning of this paper, a basic software structure to synchronize the engine crank signal and generate ignition signals will be explained. Several cases which can generate dwell timing error will be introduced based on this software structure. In addition, each impact level for each error case will be described. For cases of major error, compensation ways will be proposed in order to obtain more accurate dwell timing. The compensation ways by both microcontroller hardware and user software will be explained in detail. In conclusion, this paper will show the accuracy of ignition signal which implements proposed compensation ways that can be improved as compared to conventional ignition signal.

Heavy-duty diesel (HDD) engines are the primary propulsion source for most heavy-duty vehicle freight movement and have been equipped with an array of aftertreatment devices to comply with more stringent emissions regulations. In light of concerns about the transportation sector's influence on climate change, legislators are introducing requirements calling for significant reductions in fuel consumption and thereby, greenhouse gas (GHG) emission over the coming decades. Advanced engine concepts and technologies will be needed to boost engine efficiencies. However, increasing the engine's efficiency may result in a reduction in thermal energy of the exhaust gas, thus contributing to lower exhaust temperature, potentially affecting aftertreatment activity, and consequently rate of regulated pollutants. This study investigates the possible utilization of waste heat recovered from a HDD engine as a means to offset fuel penalty incurred during thermal management of SCR system.

International regulations continuously restrict the standards for the exhaust emissions from automotive engines. In order to comply with these requirements, innovative control and diagnosis systems are needed. In this scenario the application of methodologies based on the in-cylinder pressure measurement finds widespread applications. Indeed, almost all engine thermodynamic variables useful for either control or diagnosis can be derived from the in-cylinder pressure. Apart for improving the control accuracy, the availability of the in-cylinder pressure signal might also allow reducing the number of existing sensors on-board, thus lowering the equipment costs and the engine wiring complexity. The paper focuses on the detection of the engine thermal state, which is fundamental to achieve suitable control of engine combustion and after-treatment devices.

Following the development of new technologies in Vehicle Thermal Management aiming to both enhancing the MAC System efficiency and reducing the thermal load to be managed, a prediction tool based on the AMEsim platform was developed at Advanced PD EMEA. This tool is dedicated to predict the effect of the implementation of sensors monitoring both the relative humidity and the carbon dioxide (CO2) concentration (taking into account passengers' generated moisture and CO2). This model implemented with the usual comfort inputs (CO2 and RH acceptable ranges) considers the system variables influencing the comfort and predicts the increase of both RH and CO2 concentration in the cabin compartment in any driving cycle depending on the number of occupants.

When selecting a transmission gear, it has been standard to shift by operating a lever-type gear selector, but with advances in transmission technology and vehicle control, there is currently demand for technical progress in the operating method of the gear selector, and a good balance between intuitive operation by users and prevention of accidental operation is required. The authors have developed a push button-type electrically controlled gear selector that makes shifting easy to master and enables intuitive operation. A push button-type shifter should essentially be suitable for intuitive operation, but difficulty in distinguishing between selections has been an issue. However, we posited that distinguishing gear position selections by differentiating button operation direction as well as button positioning and shape could be implemented effectively. Through verification with test subjects, we have confirmed that this shift selector is intuitive and helpful in mastering operation.