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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.

A variation in the camber of an automotive wheel is desired to compensate a side-slip force change owing to normal load transfer when the car is cornering. The camber of a steered wheel can be varied by adjusting caster or lean angle which are the representations of steering axis orientation. Thus, a smart camber can be created by a variable caster or lean angle. Choosing which parameter among the two angles to be variable is very important and dependent on its different effects. Here, homogeneous transformation is employed to establish camber as a function of caster, lean angle, and steering angle in the general case. A comparison between caster and lean angle based on different criteria is then made. The comparison shows that a variable caster is much better and more feasible than a variable lean angle in generating a smart camber.

The paper discusses the benefits of a four stroke engine having one intake and one exhaust rotary valve. The rotary valve has a speed of rotation half the crankshaft and defines an open passage that may permit up to extremely sharp opening or closing and very large gas exchange areas. The dual rotary valve design is applied to a racing engine naturally aspirated V-four engine of 1000cc displacement, gasoline fuelled with central direct injection and spark ignition. The engine is then modeled by using a 1D engine & gas dynamics simulation software package to assess the potentials of the solution. The improved design produces much larger power densities than the version of the engines with traditional poppet valves revving at higher speeds, with reduced frictional losses, and with larger gas exchange areas while also improving the fuel conversion efficiency thanks to the sharpness of opening or closing events.

A unified approach to cooperative and non-cooperative Detect-and-Avoid (DAA) is a key enabler for Remotely Piloted Aircraft System (RPAS) to safely and routinely access all classes of airspace. In this paper state-of-the-art cooperative and non-cooperative DAA sensor/system technologies for manned aircraft and RPAS are reviewed and the associated multi-sensor data fusion techniques are discussed. A DAA system architecture is presented based on Boolean Decision Logics (BDL) for selecting non-cooperative and cooperative sensors/systems including both passive and active Forward Looking Sensors (FLS), Traffic Collision Avoidance System (TCAS) and Automatic Dependent Surveillance - Broadcast (ADS-B). After elaborating the DAA system processes, the key mathematical models associated with both non-cooperative and cooperative DAA functions are presented.

The paper presents a novel design for a two stroke thermal engine that delivers excellent fuel economy and low emissions within the constraints of today's cost, weight and size. The engine features asymmetrical port timing through a novel translating and rotating piston mechanism. The engine is externally scavenged and supercharged, has wet sump and oil pressure lubrication, direct injection, it is lightweight, easy to build, with minimal number of parts, low production cost, ability to be balanced and compact design. The two stroke mechanism produces a linear motion of the pistons as well as an elliptical path on the surface of the cylinder. This allows the piston to sweep as well as travel past the ports. Suitable slots around the raised lip of the piston generate the asymmetry that makes the exhaust port to open first and to close first. The inlet port remains open to complete the cylinder charging and allow supercharging. Direct fuel injection is adopted for best results.

Hydrogen Internal Combustion Engine (ICE) vehicles using a traditional ICE that has been modified to use hydrogen fuel are an important mid-term technology on the path to the hydrogen economy. Hydrogen-powered ICEs that can run on pure hydrogen or a blend of hydrogen and compressed natural gas (CNG) are a way of addressing the widespread lack of hydrogen fuelling infrastructure in the near term. Hydrogen-powered ICEs have operating advantages as all weather conditions performances, no warm-up, no cold-start issues and being more fuel efficient than conventional spark-ignition engines. The Wankel engine is one of the best ICE to be converted to run hydrogen. The paper presents some details of an initial investigation of the CAD and CAE modeling of a novel design where two jet ignition devices per rotor are replacing the traditional two spark plugs for a faster and more complete combustion.

As computational methodologies become more integrated into industrial vehicle pre-development processes the potential for high transient vehicle thermal simulations is evident. This can also been seen in conjunction with the strong rise in computing power, which ultimately has supported many automotive manufactures in attempting non-steady simulation conditions. The following investigation aims at exploring an efficient means of utilizing the new rise in computing resources by resolving high time-dependent boundary conditions through a series of averaging methodologies. Through understanding the sensitivities associated with dynamic component temperature changes, optimised boundary conditions can be implemented to dampen irrelevant input frequencies whilst maintaining thermally critical velocity gradients.

The paper presents a novel concept of a very efficient transportation engines for operation with CNG, LNG or LPG. The paper considers the options of single fuel design with jet ignition and dual fuel design with Diesel and gas. In the first option gas fuel is injected into the main chamber by a direct injector and ignited by jet ignition. In the second option gas fuel is injected into the main chamber by a direct injector and ignited by the direct injection of a small quantity of Diesel fuel. Injection and ignition may be tuned to control the amount of premixed and diffusion combustion to produce the best fuel conversion efficiency vs. load and speed requirements within the prescribed pressure and temperature constraints.

The paper presents a novel concept of very efficient transportation engines for operation with CNG, LNG or LPG. The combustion system permits mixed diesel/gasoline-like operation changing the load by quantity of fuel injected and modulating the premixed and diffusion combustion phases for high fuel energy transfer to piston work. A waste heat recovery system (WHRS) is then recovering the intercooler and engine coolant energy plus the exhaust energy. The WHRS uses a power turbine on the exhaust and a steam turbine feed by a single loop turbo-steamer. The WHRS is the enabler of much faster warm up of the engine and further improvements of the top fuel conversion efficiency to above 50% for the specific case with reduced fuel efficiency penalties changing the load or the speed.

An accurate aeroelastic assessment of powered HALE aircraft is of paramount importance considering that their behaviour contrasts the one of conventional aircraft mainly due to the use of high aspect-ratio wings with distributed propulsion systems. This particular configuration shows strong dependency of the wing natural frequencies to the propulsion distribution and operating conditions. Numerical and experimental investigations are carried out to better understand the behaviour of flexible wings, focusing on the effect of distributed electric propulsion systems. Several configurations are investigated, including a single propulsion system using an engine pod (a weight with embedded electric motor, a propeller, and the wing-attached structure) installed at selected spanwise positions, and configurations with two and three propellers.

The air entrainment process of a compressed natural gas transient fuel jet was investigated in a constant-volume chamber using Schlieren and particle image velocimetry (PIV) techniques. A new method of calculating air entrainment around a gaseous fuel jet is proposed using Schlieren and PIV imaging techniques. This method offers an alternative to calculation of an alternative to calculation of entrainment using LIF technique in gaseous fuel jets. Several Jet-ambient pressure ratios were tested. In each test, nitrogen was used to fill the chamber as an air surrogate before the jet of natural gas was injected. Schlieren high speed videography and PIV experiments were performed at the same conditions. Schlieren mask images were used to accurately identify the jet boundary which was then superimposed onto a PIV image. Vectors adjacent to the Schlieren mask in the PIV image were used to calculate the spatial distribution of the air entrainment at the jet boundary.

The paper presents experimental analysis of the airflow around the differential center housing of a rear drive full-scale passenger car. The study included investigation of local airflow total and static pressure, as well as surface flow visualization. Estimation of the local airflow velocity is based on the measured pressure coefficients. The experiments were carried out at different test facilities: in a climatic wind tunnel, in a full-scale wind tunnel and on-road. Influence of side wind was modeled by the yawing of the car in the full-scale wind tunnel. The results show the asymmetrical structure of the flow in both, vertical and horizontal planes. Estimated longitudinal relative local velocity decreases from maximum Vr ≈ 0.4 at the lower surface of the center housing, to about Vr ≈ 0 above the upper surface. Side wind increases airflow velocity around the center housing within the investigated yaw range ± 20°

The flight simulation of airships and hot air balloons usually considers the envelope geometry as a fixed shape, whose volume is eventually reduced by ballonets. However, the dynamic pressure or helium leaks in airships, and the release of air to allow descent in hot air balloons can significantly change the shape of the envelope leading to potential dangerous situations. In fact, in case of semi-rigid and non-rigid airships a reduction in envelope internal pressure can reduce the envelope bending stiffness leading to the loss of the typical axial-symmetric shape. For hot air balloons thing goes even worse since the lost of internal pressure can lead to the collapsing of the balloon shape to a sort of vertically stretched geometry (similar to a torch) which is not able to sustain the attached basket and its payload.

Within the pre-development phase of a vehicle validation process, the role of computational simulation is becoming increasingly prominent in efforts to ensure thermal safety. This gain in popularity has resulted from the cost and time advantages that simulation has compared to experimental testing. Additionally many of these early concepts cannot be validated through experimental means due to the lack of hardware, and must be evaluated via numerical methods. The Race Track Simulation (RTS) can be considered as the final frontier for vehicle thermal management techniques, and to date no coherent method has been published which provides an efficient means of numerically modeling the temperature behavior of components without the dependency on statistical experimental data.

Compressed natural gas (CNG) is an attractive, alternative fuel for spark-ignited (SI), internal combustion (IC) engines due to its high octane rating, and low energy-specific CO2 emissions compared with gasoline. Directly-injected (DI) CNG in SI engines has the potential to dramatically decrease vehicles’ carbon emissions; however, optimization of DI CNG fueling systems requires a thorough understanding of the behavior of CNG jets in an engine environment. This paper therefore presents an experimental and modeling study of DI gaseous jets, using methane as a surrogate for CNG. Experiments are conducted in a non-reacting, constant volume chamber (CVC) using prototype injector hardware at conditions relevant to modern DI engines. The schlieren imaging technique is employed to investigate how the extent of methane jets is impacted by changing thermodynamic conditions in the fuel rail and chamber.

Kinetic energy recovery systems (KERS) placed on one axle coupled to a traditional thermal engine on the other axle is possibly the best solution presently available to dramatically improve the fuel economy while providing better performances within strict budget constraints. Different KERS may be built purely electric, purely mechanic, or hybrid mechanic/electric differing for round trip efficiency, packaging, weights, costs and requirement of further research and development. The paper presents an experimental analysis of the energy flow to and from the battery of a latest Nissan Leaf covering the Urban Dynamometer Driving Schedule (UDDS). This analysis provides a state-of-the-art benchmark of the propulsion and regenerative braking efficiencies of electric vehicles with off-the-shelve technologies.

As part of the current initiatives aimed at enhancing safety, efficiency and environmental sustainability of aviation, a significant improvement in the efficiency of aircraft operations is currently pursued. Innovative Communication, Navigation, Surveillance and Air Traffic Management (CNS/ATM) technologies and operational concepts are being developed to achieve the ambitious goals for efficiency and environmental sustainability set by national and international aviation organizations. These technological and operational innovations will be ultimately enabled by the introduction of novel CNS/ATM and Avionics (CNS+A) systems, featuring higher levels of automation. A core feature of such systems consists in the real-time multi-objective optimization of flight trajectories, incorporating all the operational, economic and environmental aspects of the aircraft mission.

This paper introduces the Seabus SB-8, a new Wing-In-Ground-Effect (WIGE) craft designed for 8 - 10 passengers. The craft will be used for fast transportation across Port Phillip Bay in Melbourne, Australia. With a cruise speed of about 140 km/hr, it can cross the bay in 30 min as compared to 75 min for land transportation. Computational Fluid Dynamics (CFD) analysis was conducted on the design to determine aerodynamic properties at various angles of attack and operating heights. The influence of ground effect was also determined as well as the effect of Centre of Gravity (CG) position on longitudinal stability. Using flow visualization areas of potential flow separation were identified and interactions of wake vortices with different parts of the aircraft were determined. Note that some aspects of the design are proprietary.

The paper presents a survey of the opportunities to convert compression ignition heavy duty truck engines to work on single or dual fuel modes with CNG. In one popular option, the compression ignition engine is converted to spark ignition with throttle load control and port injection of the CNG. In another option of increasing popularity, the LNG is directly injected and ignited by direct injection of pilot Diesel. This latter option with direct injection of natural gas and diesel through separate injectors that are fully independent in their operation is determined to be the most promising, as it is expected to deliver better power density and similar part load fuel economy to Diesel.

The design of a longitudinal stability augmentation system (SAS) for an aircraft with reduced tail size in the preliminary design phase is presented. Reducing tail size will reduce drag and weight and result in better fuel consumption, but it will reduce the level of stability. A control law is designed to give the aircraft the same stability level as that with the initial tail size. The feedback gains of the control law is computed with the equivalent stability derivative criteria of and CmαCmq . The paper also gives an overview of classical root locus and pole placement method and demonstrates that equivalent stability derivative criteria is suitable for preliminary aircraft design applications. Moreover, the control laws are also synthesized using robust control LQG/LTR which can be elaborated more in the detail design phase.