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The incorporation of hydrogen fuel cells into heavy duty tactical mobility vehicles can bring about great opportunities in reducing the pollutant emissions of this kind of platforms (GVW > 30,000 kg). Furthermore the transportation of fuel to operational areas has become a key aspect for any deployment therefore optimal use of this resource is of paramount importance. Finally, it is also quite common for such platforms to serve additional purposes, besides freight delivery, such as powering external equipment (i.e. field hospitals or mobile artillery pieces). This work will describe the intelligent energy management system for a PEM Fuel Cell-Battery-Ultracapacitor Hybrid 8×8 heavy truck of the aforementioned weight class which also contemplates an internal electric/traction power generation unit. It will describe how the system optimizes the use of battery and hydrogen fuel energy while keeping system efficiency and performance at a maximum.

In a multi-pass weld, the development of residual stress to a large extent depends on the response of the weld metal, heat affected zone and parent material to complex thermo-mechanical cycles during welding. Previous investigations on this subject mostly focused on mechanical tensioning or heat treatment to modify the residual stress distribution in and around the weld. In this research, microstructural refinement with modification of residual stress state was attempted by applying post weld cold rolling followed by laser processing. The hardening of the weld metal was evaluated after welding, post weld cold rolling and post weld cold rolling followed by laser processing. The residual stress was determined non-destructively by using neutron diffraction. Hardness results showed evidence of plastic deformation up to 4 mm below the weld surface.

Energy management strategies greatly influence the power performance and fuel economy of series hybrid electric tracked bulldozers. In this paper, we present a procedure for the design of a power management strategy by defining a cost function, in this case, the minimization of the vehicle’s fuel consumption over a driving cycle. To explore the fuel-saving potential of a series hybrid electric tracked bulldozer, a dynamic programming (DP) algorithm is utilized to determine the optimal control actions for a series hybrid powertrain, and this can be the benchmark for the assessment of other control strategies. The results from comparing the DP strategy and the rule-based control strategy indicate that this procedure results in approximately a 7% improvement in fuel economy.

The interactions between automatic controls, physics, and driver is an important step towards highly automated driving. This study investigates the dynamical interactions between human-selected driving modes, vehicle controller and physical plant parameters, to determine how to optimally adapt powertrain control to different human-like driving requirements. A cyber-physical system (CPS) based framework is proposed for co-design optimization of the physical plant parameters and controller variables for an electric powertrain, in view of vehicle’s dynamic performance, ride comfort, and energy efficiency under different driving modes. System structure, performance requirements and constraints, optimization goals and methodology are investigated. Intelligent powertrain control algorithms are synthesized for three driving modes, namely sport, eco, and normal modes, with appropriate protocol selections. The performance exploration methodology is presented.

Global aviation is growing exponentially and there is a great emphasis on trajectory optimization to reduce the overall environmental impact caused by aircraft. Many optimization techniques exist and are being studied for this purpose. The CLEAN SKY Joint Technology Initiative for aeronautics and Air transport, a European research activity run under the Seventh Framework program, is a collaborative initiative involving industry, research organizations and academia to introduce novel technologies to improve the environmental impact of aviation. As part of the overall research activities, “green” aircraft trajectories are addressed in the Systems for Green Operations (SGO) Integrated Technology Demonstrator. This paper studies the impact of large commercial aircraft trajectories optimized for different objectives applied to the on board systems.

The paper presents an innovative approach for the functional specification of complex and highly integrated aircraft control systems, such as the Environmental Control System (ECS), by applying model based specification methods. Complexity and effectiveness of modern ECS have significantly increased during the last few years along with development of new technologies and innovations in control engineering as well as digital data distribution and processing. Efficient management of cabin air flows on the one hand makes the ECS more energy-saving and on the other hand more complex with regard to its functionality and interaction with other interfaced aircraft systems. Numerous data interfaces to other systems and a high degree of automation are typical for a modern ECS. The aircraft manufacturer specifies the entire ECS functions and its interactions within the aircraft.

The work describes a concept application that aids a safety engineer to create a layup of equipment models by using an image scan of a schematic and a library of predefined standard component and their symbols. The approach uses image recognition techniques to identify the symbols within the scanned image of the schematic from a given library of symbols. Two recognition approaches are studied, one uses General Hough Transform; the other is based on pixel-level feature computation combining both structure and statistical features. The application allows the user to accept or edit the results of the recognition step and allows the user to define new components during the layup step. The tool then generates an output file that is compatible with a formal safety modeling tool. The identified symbols are associated to behavioral nodes from a model based safety tool.

The work describes a concept application to aid a safety engineer to perform an audit of a production aircraft against safety driven installation requirements. The capability is achieved using the following steps: A) Image capture of a product and measurement of distances between datum points within the product with/without references to a planar surface B) A digital reconstruction of the fabricated product by using multiple captured images to reposition parts according to the actual model. C) The projection onto the 3D digital reconstruction of the safety related installation constraints, respecting the original intent of the constraints that are defined in the digital mock-up.

The vision of SESAR is to integrate and implement new technologies to improve air traffic management (ATM) performance. Enhanced automation and new separation modes characterize the future concept of operations, where the role of the human operator will remain central by integrating more managing and decision-making functions. The expected changes represent challenges for the human actors in the aircraft and on ground and must be taken into account during the development phase. Integrating the human in the ATM system development starting from the early design phase is a key factor for future acceptability. This paper describes the adaptation of currently applied Cockpit Human Factors processes in order to be able to design the aircraft for the future ATM environment.

The Environmental Control System is a relevant element of any conventional or More Electric Aircraft (MEA). It is either the key consumer of pneumatic power or draws a substantial load from the electric power system. The objective of this paper is to present a tool for the design of Environmental Control Systems and to apply it to an unconventional system. The approach is based on a recently proposed methodology, which is improved with respect to flexibility and ease-of-use. Furthermore, modeling and simulation of vapor compression cycles is discussed, which are candidate technological solutions for More Electric Aircraft concepts. A steady-state moving boundary method is presented to model heat exchangers for such applications. Finally, the resulting design environment is applied to optimization of an unconventional ECS architecture and exemplary results are presented.

This paper discusses the design of a model-based fault detection scheme for robust and early detection of runaways in aircraft control surfaces servo-loop. The proposed scheme can be embedded within the structure of in-service monitoring systems as a part of the Flight Control Computer (FCC) software. The final goal is to contribute to improve the performance detection of unanticipated runaway faulty profiles having very different dynamic behaviors, while retaining a perfect robustness. The paper discusses also the tradeoffs between adequacy of the technique and its implementation level, industrial validation process with Engineering support tools, as well as the tuning aspects. The proposed methodology is based on a combined data-driven and system-based approach using a dedicated Kalman filtering. The technique provides an effective method ensuring robustness and good performance (well-defined real-time characteristics and well-defined error rates).

Industrial requirements imply optimizing the development cycle, reducing manufacturing costs and reaching marketable product maturity as fast as possible. The design stage often involves multiple sites and various partners. In this context, the use of computer simulation becomes absolutely necessary to meet industrial needs. Nevertheless, this activity can be effective only if it is integrated correctly in the industrial organization. In the aeronautical and space systems industry, mechanical specifications often require the use of composites reinforced by continuous carbon fibers. The goal of this article is to describe how, on a time frame of nearly twenty years, a series of scientific and technical tasks were carried out in partnership in order to develop, validate and implement Resin Transfer Molding (RTM) flow simulation and cure analysis for high performance composites. The research stage started at the university in 1991.

The paper describes the methodology of contact problem solving that is used in specialized software code aimed at simulation of aircraft assembly process. For considered class of problems it is possible to radically reduce the number of unknowns without loss of accuracy. The results of validation of developed code against physical experiments and commercial FEM codes are also given.

Airbus is a leading aircraft manufacturer with the position as technology driver and a distinct customer orientation, broad commercial know-how and high production efficiencies. It is constantly working on further and new development of its products from ecological and economical points of view. Fuel Cell Systems (FCS) on board of an aircraft provide a good opportunity to address both aspects. Based on existing and upcoming research results it is necessary to find trend-setting measures for the industrial implementation and application of this technology. Past and current research efforts have shown good prospects for the industrial implementation and application of the fuel cell technology. Being an efficient source of primarily electric power the fuel cell would be most beneficial when used in conjunction with electrical systems.

The quantitative assessment and comparison of different hybrid vehicle options has traditionally been done on the basis of measuring or estimating the vehicle's fuel economy over predefined drive-cycles. In general, little or no consideration has been given to the more subjective and difficult to quantify vehicle requirements, such as trying to understand which derivative will be the most “fun” vehicle to drive. A lack of understanding in this area of vehicle performance sufficiently early within the development life-cycle so as to be in a position to influence the vehicle design, can lead to a compromised powertrain architecture which will ultimately increase the risk of product failure. The work presented within this paper constitutes part of the overall design activities associated with the LIFECar programme. The aim of the LIFECar consortium is to manufacture a lightweight, fuel cell hybrid electric sports vehicle.

Electroimpact has developed a new Fastener Feed System which provides an automated solution for fasteners previously hand fed via drop tubes. The hardware is simple, compact, and is supplied a fraction of the cost of hoppers or cartridges. It can be used as a primary feed system or it can be used as an auxiliary feed system when combined with feed systems designed for high quantities of fasteners. We have installed this system on the A380 Stage 0 LVER lower panel wing machines and feed 5 diameters, 10 grips each, for a total of 50 different fastener types. This system moves 547 total fasteners per ship set from manual feed to automatic feed, saving considerable build time.

This paper describes the Airbus plans to use ADS-B in the future concept of operations in both the European SESAR and the US NEXTGEN concepts of operations. It details the different steps that are currently considered by Airbus roadmap to deploy ADS-B services and functions. In particular, the following points are described: Use of ADS-B OUT in Non Radar Airspace Use of ADS-B IN and the associated Airbus functions to offer a better Air Traffic Situation Awareness (ATSAW) package: the various applications for airborne, in trail climb/descent procedures or enhanced visual acquisition are particularly detailed. Use of ADS-B for the future Spacing function as currently considered in the initial ASAS implementation for SESAR: the three “Remain Behind”, “Merge at Waypoint then Remain behind” and the “Heading then merge behind” applications are explained.

The application of hybridization technology is now widely regarded as a significant step forward to reduce fuel consumption and hence CO₂ emissions for ground vehicles. Many programs and much research has been done on these technologies in the automotive market, however little work has been done in the very cost sensitive market sector of the small motorcycle. This paper introduces and discusses the application of a low-cost hybrid technology to small motorcycles and scooters, and reviews some of the initial trade-offs through the use of a new hybrid simulation model developed at Cranfield University. The study being presented assessed the existing Energy Storage Systems (ESS) in the market. This list was reduced, omitting options which posed a clear safety or cost risk, or solutions which would disproportionally increased the Gross Vehicle Weight (GVW). Also omitted were storage options which could not be production ready in the near term, 3 - 5 years.

This paper gives an overview of the development of a number of loss models for the pushing metal V-belt CVT. These were validated using a range of experimental data collected from two test rigs. There are several contributions to the torque losses and new models have been developed that are based upon relative motion between belt components and pulley deflections. Belt slip models will be proposed based upon published theory, expanded to take account of new findings from this work. The paper introduces a number of proposals to improve the efficiency of the transmission based on redesign of the belt geometry and other techniques to reduce frictional losses between components. These proposed efficiency improvements have been modelled and substituted into a complete vehicle simulation to show improvements in vehicle fuel economy over a standard European drive cycle.

As the essential of future driver assistance system, brake-by-wire system is capable of performing autonomous intervention to enhance vehicle safety significantly. Regenerative braking is the most effective technology of improving energy consumption of electrified vehicle. A novel brake-by-wire system scheme with integrated functions of active braking and regenerative braking, is proposed in this paper. Four pressure-difference-limit valves are added to conventional four-channel brake structure to fulfill more precise pressure modulation. Four independent isolating valves are adopted to cut off connections between brake pedal and wheel cylinders. Two stroke simulators are equipped to imitate conventional brake pedal feel. The operation principles of newly developed system are analyzed minutely according to different working modes. High fidelity models of subsystems are built in commercial software MATLAB and AMESim respectively.