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Automated solutions for manufacturing composite products based on prepreg often imply Automatic Fiber Placement or Automatic Tape Laying. These systems are generally associated with huge investments. For certain manufacturing applications it is interesting to investigate alternatives to find simpler and less costly automation. One example of an automated system could be the use of a standard industrial robot to pick single prepreg plies from an automated cutting machine and stack them to form a plane laminate. This paper is based on a case illustrating a product from the aircraft manufacturing industry. The case will demonstrate a pick and place concept on a general level and illustrate challenges that must be solved. The challenge selected to be the main focus for this paper is an automated process for backing paper removal. A literature review of different gripping technologies reveals several interesting technologies, and the most promising are tested for backing paper removal. The tests show that an automated removal process can be designed by using standard vacuum grippers in combination with mechanical clamping grippers. In order to lift the backing paper with a vacuum gripper an initial separation between the backing paper and prepreg is needed. This separation is most easily mechanically induced by bending the material. The proposed solution for automatic backing paper removal can be integrated in a manufacturing cell for manufacturing of the studied product. SAE Technical Paper 2013-01-2289

The Advanced Extra-vehicular Activity (EVA) team of the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) Crew and Thermal Systems Division (CTSD) participated in the Desert Research and Technology Study (RATS) in September 2003, at Meteor Crater, AZ. The Desert RATS is an integrated remote field site te t with team members from several NASA centers (Johnson Space Center; Glenn and Ames Research Centers) and universities (Bowling Green State University, University of Cincinnati, Massachusetts Institute of Technology) participating. Each week of the two-week field test had a primary focus. The primary test hardware for the first week was the I-Gravity Lunar Rover Training Vehicle, or Grover, which was on loan to NASA from the United States Geological Survey (USGS) Astrogeology Research Program. The 2003 Grover driving test results serve as a rover performance characterization baseline for the Science, Crew, Operation and Utility Testbed (SCOUT) project team, which will be designing and fabricating a next generation roving vehicle prototype in Fiscal Year (FY) 2004. The second week of testing focused on EVA geologic traverses that utilized a geologic sample field analysis science trailer and also focused on human-robotic interaction between the suited subjects and the EVA Robotic Assistant (ERA). This paper will review the Advanced EVA team's role in the context of the overall Desert RATS, as well as the EVA team results and lessons learned. For information regarding other test participants' results, the authors can refer interested parties to the test reports produced by those Desert RATS teams.

Progres dans la conception et la fabrication de materiaux de friction en papier pour lourdes charges

This paper clarifies aggressivity reduction approach for MPV, Multi-Purpose Vehicles, derived from large passenger vehicles toward small passenger vehicles. The effects of aggressivity-reducing approach were measured through full-frontal rigid barrier crash simulations with TRL aluminum honeycomb by Finite Element Method. The front-end structures of large vehicles studied in this paper based on this aggressivity reduction approach show good front-end homogeneity and low average height of force. The structures were also found to effectively reduce aggressivity toward small vehicles by car-to-car simulation. However, there are some cases where the effect was influenced by overlap ratios. From this result, overlap ratio is considered to be one of the important factors to improve compatibility performance.

A comparison of the NHTSA advanced dummy and the Hybrid III is presented in this paper based on their performance in repeated sled tests under 3 different restraint systems. The restraint systems considered are: the airbag alone, the 3-point belt alone, and a combined use of the airbag and the 3-point belt. Various time-histories pertaining to accelerations, angular velocities, deflections and forces have been compared between the two dummies in order to study their repeatability. The Hybrid III appears to be more repeatable than the NHTSA advanced dummy in its response in one case, that of restraint with the 3-point belt alone. The response of the NHTSA advanced dummy in two other restraint modes, the airbag alone and the combination of 3-point belt and airbag, appears to be no less repeatable than that of Hybrid III in this series of tests. The variability in the sled pulse appears to mask the differences, if any, in the variability of response between the two dummies in two later cases. Under some restraint configurations, for some body segments, the NHTSA advanced dummy appears to show better repeatability. In addition, it appears that the read-out of the chest-deflection measurement system in the NHTSA advanced dummy is not well defined because it is influenced by the rotation of the upper spine relative to the lower spine. (A) For the covering abstract see ITRD E106439.

Wheat is a candidate crop for the Advanced Life Support (ALS) system, and cereal grains and their products will be included on long-term space missions beyond low earth orbit. While the exact supply scenario has yet to be determined, some type of post-processing of these grains must occur if they are shipped as bulk ingredients or grown on site for use in foods. Understanding the requirements for processing grains in space is essential for incorporating the process into the ALS food system. The ESM metric developed by NASA describes and compares individual system impact on a closed system in terms of a single parameter, mass. The objective of this study was to compare the impact of grain mill type on the ESM of producing yeast and flat breads. Hard red spring wheat berries were ground using a Brabender Quadrumat Jr. or the Kitchen-Aid grain mill attachment (both are proposed post-harvest technologies for the ALS system) to produce white and whole wheat flour, respectively. Yeast bread was made using three methods (hand+oven, bread machine, mixer with dough hook attachment + oven). Flat bread was made using four methods (hand+oven, hand+griddle, mixer+oven, mixer+griddle). Data on all inputs (active time, passive time, mass and volume of ingredients and equipment, power) were measured and used to calculate ESM. Assumptions were based on data in NASA documents. Data were analyzed using PC-SAS with significance at P < 0.05. Grain mill type significantly (P < 0.05) influenced the ESM of making both bread types; and the Brabender Quadrumat Jr. contributed significantly (P < 0.05) more mass than the Kitchen-Aid grain mill to the ESM for producing both types of bread. Results can be used by systems analysts to define energy and volume requirements for the food system and by researchers to select and modify food production scenarios.

The effects of API SE engine oils on the activity of a 1975 prototype monolithic, noble metal oxidation catalyst have been studied in long-term multicylinder laboratory engine tests. Results of this work showed that oil consumption rates, up to 1 qt/100 miles, and lube ash up to 1.6%, do not significantly affect catalyst activity in 500 hour tests, equivalent to 20,000 miles (32,180 km). A higher-than-normal phosphorus-containing oil (0.32% P) caused significant loss in catalyst activity after testing for 30,000 miles (48,270 km). This suggests that any need for increased phosphorus-containing additives in future oils could cause catalyst poisoning before 50,000 miles.

For the past thirty years heavy duty diesel oil performance has been defined by the API CD category type tests. During this time the trend in CD oils has been toward lower ash and lower TBN. This has been largely due to the performance improvements of ashless components which now form a major part of today's HD formulations. PC-1 type category testing indicates that ashless components will continue to be effective in meeting these higher heavy duty diesel targets. As a result, lower ash PC-1 type formulations are feasible. Oils have been developed using the dynamometer engine tests currently being worked with to define PC-1 to meet the target of improved oil consumption. These oils are also showing similar advantages in field performance testing over current CD/SF quality lubricants.

A line of high-quality multigrade diesel engine oils suitable for long drain applications has been developed using hydrotreated base stock. To meet the growing demand for lubricants in Canada and to offset the high degree of reliance on imports, a new lubricant facility has been constructed in the Toronto area. The facility employs a process in which feedstock undergoes very severe hydrogenation under high pressure. Products are then fractionated, dewaxed, and again hydrogenated under more moderate conditions. Advantages of the hydrotreating process include increased yield, greater flexibility in producing various viscosity grades, and less dependence on selected lubricant crude sources. Two hydrotreated base stocks were used to conduct necessary product development prior to introducing the new lubricant facility. Laboratory and engine dynamometer tests indicated that lubricating oils using hydrotreated base stock had superior control of diesel piston deposits and oxidative viscosity increase. Excellent performance of multigrade diesel engine oils using both hydrotreated and solvent-refined base stock over extended oil change intervals was demonstrated in extensive field trials. Cold weather benefits for multigrade diesel engine oils were defined by cold room studies and outdoor trials. Low volatility, high thermal stability, and good additive response were particular features contributing to overall performance improvements. Finished lubricants formulated from hydrotreated base stocks of similar viscosity index appeared to have similar performance characteristics, regardless of crude source.

Alongside with the increasing vehicle complexity, the functionalities related to the safety, diagnosis and maintainability have become critical. The operators of special machines such as agricultural, mining, construction vehicles might be overwhelmed by this increased complexity and, as a result, operations for the recovery or maintenance of their vehicles become difficult. The Augmented Reality (AR) seems to be a very promising technology both if applied to traditional smart-phones or to the upcoming glasses, that has been just presented to the market by several manufacturers. This paper reviews some use cases of applications created in Institute for Agricultural and Earthmoving Machines (IMAMOTER) of the National research Council of Italy (CNR) engineers laboratories, which propose a novel approach for assisted maintenance, recovery or training. These take advantage of the use of AR, providing an efficient method for user fast learning of simple procedures as well as a support for fault recovery and maintenance in hazardous environments or work places. In the first application scenario, the AR is used to recognize the dashboard and the machine controls in order to provide further information about them. In the second scenario the AR application is connected with a CAN-Bluetooth gateway to the SAE J1939 network and provides real-time information or messages in case of faults or anomalous conditions. Finally, a real implementation of AR technologies will be presented, that leads the user during recovery procedures, such a fuse replacement in three simple steps. The paper presents real Apps and future perspectives in the application of AR technology in Heavy-Duty vehicles.

The use of direct injection (DI) engines allows a more precise control of the air-fuel ratio, an improvement of fuel economy, and a reduction of exhaust emissions thanks to the ultra-lean combustion due to the charge stratification. These effects can be partially obtained also with an optimized Air Direct Injection that permits to increase the turbulence at low speed and load increasing the combustion stability especially in lean condition. In this paper, a gasoline PFI (named G-PFI), gasoline PFI-methane DI dual fuel (named G-MDF) lean combustion were analyzed. The G-MDF configuration was also compared with a gasoline PFI - air DI (named G-A) configuration in order to distinguish the chemical effect of methane from the direct injection physical effect. The tests were carried out in a small displacement PFI/DI SI engine. The experimental investigation was carried out in a transparent small single-cylinder, spark ignition four-stroke engine. It was equipped with the cylinder head of a Direct Injection 244 cc engine. The in-cylinder pressure was measured and the indicated mean effective pressure, IMEP, and its CoV were evaluated. 2D-digital imaging optical measurements were performed to analyze the combustion process with high spatial and temporal resolution. In particular, it allows to follow the flame evolution and evaluate the flame front propagation speed. The CO, CO2, HC and NOx emissions were characterized at the exhaust by means of gaseous analyzers. The measurements were performed at 2000 rpm PL in steady state condition. The G-MDF as well as the G-A configurations allow improving the vaporization of the heavy gasoline compound and the homogenization of the charge. Moreover, for the G-MDF, the presence of the methane and its chemical interaction with gasoline heavy hydrocarbon enhances a more efficient combustion

Enhanced calibration strategies and innovative engine combustion technologies are required to meet the new limits on exhaust gas emissions enforced in the field of marine propulsion and on-board energy production. The goal of the paper is to optimize the control parameters of a 4.2 dm3 unit displacement marine DI Diesel engine, in order to enhance the efficiency of the combustion system and reduce engine out emissions. The investigation is carried out by means of experimental tests and CFD simulations. For a better control of the testing conditions, the experimental activity is performed on a single cylinder prototype, while the engine test bench is specifically designed to simulate different levels of boosting. The numerical investigations are carried out using a set of different CFD tools: GT-Power for the engine cycle analysis, STAR-CD for the study of the in-cylinder flow, and a customized version of the KIVA-3V code for combustion. All the models are calibrated through the above mentioned experimental campaign. Then, CFD simulations are applied to optimize the injection parameters and to explore the potential of the Miller combustion concept. It is found that the reduction of the charge temperature, ensuing the adoption of an early intake valve closing strategy, strongly affects combustion. With a proper valve actuation strategy, an increase of boost pressure and an optimized injection advance, a 40% reduction of NOx emissions can be obtained, along with a significant reduction of in-cylinder peak pressure, without penalizing fuel efficiency.

[EN] To face the current challenges of the automotive industry, there is a need for computational models capable to simulate the engine behavior under low-temperature and low-pressure conditions. Internal combustion engines are complex and have interconnected systems where many processes take place and influence each other. Thus, a global approach to engine simulation is suitable to study the entire engine performance. The circuits that distribute the hydraulic fluids -liquid fuels, coolants and lubricants- are critical subsystems of the engine. This work presents a 0D model which was developed and set up to make possible the simulation of hydraulic circuits in a global engine model. The model is capable of simulating flow and pressure distributions as well as heat transfer processes in a circuit. After its development, the thermo-hydraulic model was implemented in a physical based engine model called Virtual Engine Model (VEMOD), which takes into account all the relevant relations among subsystems. In the present paper, the thermo-hydraulic model is described and then it is used to simulate oil and coolant circuits of a diesel engine. The objective of the work is to validate the model under steady-state and transient operation, with focus on the thermal evolution of oil and coolant. For validation under steady-state conditions, 22 operating points were measured and simulated, some of them in cold environment. In general, good agreement was obtained between simulation and experiments. Next, the WLTP driving cycle was simulated starting from warmed-up conditions and from ambient temperature. Results were compared with the experiment, showing that modeled trends were close to those experimentally measured. Thermal evolutions of oil and coolant were predicted with mean errors between 0.7 °C and 2.1 °C. In particular, the warm-up phase was satisfactorily modeled., This research has been partially funded by the European Union’s Horizon 2020 Framework Programme for research, technological development and demonstration under grant agreement 723976 (“DiePeR”) and by the Spanish government under the grant agreement TRA2017-89894-R. Josep SalvadorIborra was supported by Universitat Politècnica de València through the contract FPI-S2-2016-1357 of the program PAID01-16. The authors wish to thank Renault SAS, especially P. Mallet and E. Gaïffas, for supporting this research. Jaime Monfort San Segundo is acknowledged for his helpful collaboration in the code implementation

Drag reduction technologies in aircraft design are the key enabler for reducing emissions and for sustainable growth of commercial aviation. Laminar wing technologies promise a significant benefit by drag reduction and are, therefore, under investigation in various European projects. However, of the established moveable concepts and high-lift systems thus far most do not cope with the requirements for natural laminar flow wings. To this aim, new leading edge high-lift systems have been the focus of research activities in the last 5 years. Such leading edge devices investigated in projects include a laminar flow-compatible Kruger flap (Schlipf (2011) Insect shielding Kruger—structural design for a laminar flow wing. In: DGLR Congress 2011, Bremen, pp 55–60) and the Droop Nose concept (Kintscher et al. Ground testof an enhanced adaptive droop nose device. In: European Congress on Computational Methods in Applied Sciences and Engineering, ECCOMAS 2016. ECCOMAS2016—VII European Congress on Computational Methods in Applied Sciences and Engineering, 5–10 June 2016, Crete Island, Greece; Kintscher et al. Low speed wind tunnel test of a morphing leading edge. In: AIDAA—Italian Association of Aeronautics and Astronautics XXII Conference, 09–12 Sept. 2013. Neapel, Italien) and these can be considered as alternatives to the conventional slat. Hybrid laminar flow concepts are also under investigation at several research institutes in Europe (Fischer. Stepless and sustainable research for the aircraft of tomorrow—from AFloNext to Clean Sky 2. In: 1st AFloNext Workshop Key Note Lecture No. 1, Delft, The Netherlands, 10 Sept 2015). Another challenge associated with laminar wings aside from the development of leading edge movables is the need to address the control of aerodynamic shocks and buffeting as laminar wings are sensitive to high flow speeds. Here, one possible method of decreasing the wave drag caused by the aerodynamic shock is through the use of shock control bumps (SCBs). The objective of SCBs is the conversion of a single strong shock into several smaller and weaker λ-shocks resulting in a drag benefit when deployed correctly. A particular desirable characteristic of SCBs is that they should be adaptable in position and height as the shock position changes with varying conditions such as speed, altitude, and angle of attack during the flight. However, as a fixed case, SCBs can also help to control laminar buffeting by fixing the shock into given positions at the SCBs location. In this paper, a structural concept for an adaptive shock control bump spoiler is presented. Based on a concept of a fixed bump SCB spoiler, a design for an adaptive spoiler with two conventional actuators is presented. Design drivers and interdependencies of important design parameters are discussed. The presented design is simple and aims for a high TRL without adding much complexity to the spoiler. It is robust and able to form a bump with a height of 0.6% chord length which position can be adapted in a range of 10% chord. This paper is a follow-up of a previous publication (Kintscher and Monner, SAE Tech Paper 10.4271/2017-01-2164, 2017) with extending the focus by a validation of computational results by experimental tests.

This paper is a preliminary step in the direction of the definition of a radically new wing concept that has been conceived to maximize the lift even at low speeds. It is expected to equip new aerial vehicle concepts that aim to compete against helicopters and tilt rotors. They aim achieving very good performance at very low speed (5 to 30 m/s) by mean of an innovative concept of morphing ducted-fan propelled wing that has been designed to maximize the lift force. This paper presents an effective bibliographic analysis of the problem that is a preliminary necessary step in the direction of the preliminary design of the wing. A preliminary CFD evaluation allows demonstrating that the claimed results are in line with the initial expectations. According to\ud the CFD, results it has been produced a preliminary energetic evaluation of the vehicle in a flying car configuration by EMIPS method. Even if the results are still preliminary, they allow evidencing a good energy efficiency of the vehicle against helicopters.

The present paper describes an experimental and numerical study on the effect of the nozzle flow number (FN) on the full load performance of a modern Euro5 diesel automotive engine, in terms of torque, efficiency and exhaust emissions. The improvement of the diesel engine performance requires a continuous development of the engine components, first of all the injection system and in particular the nozzle design. One of the most crucial factors affecting performance and emissions is the nozzle flow number and its influence becomes more and more important as high performance and low emissions are continuous requirements. Indeed, reducing the nozzle flow number, due to an increase of spray-air mixing, an improvement in PM-NOx trade-off is generally expectable. On the other hand, at full load, where peak firing pressure and exhaust valve temperature become the limiting factors, critical operating conditions can be easily reached reducing the nozzle hole diameter. Correspondingly, spray, combustion process and pollutants formation have been numerically analyzed in details by means of 3D CFD simulations. Results indicate that full load performance are attainable for all tested nozzle configurations, but reducing the nozzle flow number, an unexpected trade-off of smoke emissions versus FN has been detected. In this respect, the numerical investigations have put into evidence the crucial role of the spray dynamics and the flame evolution during the expansion stroke.

Thermoelectric generator (TEG) has received more and more attention in its application in the harvesting of waste thermal energy in automotive engines. Even though the commercial Bismuth Telluride thermoelectric material only have 5% efficiency and 250°C hot side temperature limit, it is possible to generate peak 1kW electrical energy from a heavy-duty engine. If being equipped with 500W TEG, a passenger car has potential to save more than 2% fuel consumption and hence CO2 emission reduction. TEG has advantages of compact and motionless parts over other thermal harvest technologies such as Organic Rankine Cycle (ORC) and Turbo-Compound (TC). Intense research works are being carried on improving the thermal efficiency of the thermoelectric materials and increasing the hot side temperature limit. Future thermoelectric modules are expected to have 10% to 20% efficiency and over 500°C hot side temperature limit. This paper presents the experimental synthesis procedure of both p-type and n-type skutterudite thermoelectric materials and the fabrication procedure of the thermoelectric modules using this material. These skutterudite materials were manufactured in the chemical lab in the University of Reading and then was fabricated into modules in the lab in Cardiff University. These thermoelectric materials can work up to as high as 500°C temperature and the corresponding modules can work at maximum 400°C hot side temperature. The performance loss from materials to modules has been investigated and discussed in this paper. By using a validated TEG model, the performance improvement using these modules has been estimated compared to commercial Bisemous Telluride modules.

Mass and efficiency are key performance indicators for the development and design of future electric power systems (EPS) for more-electric aircraft (MEA). However, to enable consideration of high-level EPS architecture design trades, there is a requirement for modelling and simulation based analysis to support this activity. The predominant focus to date has been towards the more detailed aspects of analysis, however there is also a significant requirement to be able to perform rapid high-level trades of candidate architectures and technologies. Such a capability facilitates a better appreciation of the conflicting desires to maximize availability and efficiency in candidate MEA architectures, whilst minimizing the overall system mass. It also provides a highly valuable and quantitative assessment of the systemic impact of new enabling technologies being considered for MEA applications. Without this capability, predesign assessments are often time consuming and of a qualitative manner. Accordingly, this paper will present a steady state pre-design analysis tool for MEA architectures, which enables analysis of the architecture performance at different stages of the flight profile. By providing drag and drop models of key MEA electrical power system components configured for common voltage and power levels, the tool facilitates the rapid construction of candidate architectures which then enables the subsequent quantitative assessment of overall system mass and efficiency. Key to the credibility and usefulness of this tool, is the appropriate marrying of validated fundamental mathematical models (for example in the evaluation of system losses), up-to-date data driven models (for example, relating to component masses or power densities) and the flexibility to incorporate new models of technologies under consideration. The paper will describe these core elements and present selected case studies demonstrating potential uses of the tool in architecture assessment and down-selection, technology impact, and design-point sensitivity analysis.

Environmental and economic issues related to the aeronautic transport, with particular reference to the high-speed one are opening new perspectives to pulsejets and derived pulse detonation engines. Their importance relates to high thrust to weight ratio and low cost of manufacturing with very low energy efficiency. This papers presents a preliminary evaluation in the direction of a new family of pulsejets which can be coupled with both an air compression system which is currently in pre-patenting study and a more efficient and enduring valve systems with respect to today ones. This new pulsejet has bee specifically studied to reach three objectives: a better thermodynamic efficiency, a substantial reduction of vibrations by a multi-chamber cooled architecture, a much longer operative life by more affordable valves. Another objective of this research connects directly to the possibility of feeding the pulsejet with hydrogen. This paper after a preliminary analysis of the pulsejet takes into account two necessary stages of this activity with the initial definition of the starting point of this activity, which aim to define an initial thermodynamic balance of a Lenoir cycle and a preliminary but effective estimation of the thermal problem. It analyses the heat transfer process through the wall of the combustion chamber of a pulsejet for aeronautic propulsion. The inside wall is exposed to burning gases with an average temperature of 1500 K, which oscillates with an amplitude 500 k and a frequency of 50 Hz. It has been considered the possibility of using Hydrogen injection to reduce the environmental impacts at the price of introducing a cooling water envelope at an average temperature of 80 °c. The water mass flow to ensure this condition has been evaluated and it has been evaluated both the average temperature profile within the wall and the effects of the oscillations of gas temperature inside the combustion chamber. Obtained results have allowed starting an effective activity through a radically new pulsejet architecture, which is expected to outclass any former pulsejet in term of operative life and of compression ratio with a consequent step increase in terms of thermodynamic efficiency.

The emergence of wide band gap devices has pushed the boundaries of power converter operations and high power density applications. It is desirable to operate a power inverter at high switching frequencies to reduce passive filter weight and at high temperature to reduce the cooling system requirement. The paper describes the design and test of a power electronic inverter that converts a fixed input DC voltage to a variable voltage variable frequency three phase output. The component selection and design were constrained such that the inverter can operate at an ambient temperature of 170°C. The design of the key functional components such as the gate drive, power module, controller and communication will be discussed in the paper. Test results for the inverter at high temperature will also be presented.

International audience; Recent work in the area of safety analysis has shown that system Fault Trees and Failure Modes and Effects Analyses (FMEAs) can be automatically derived from a topological model of the system that has been annotated with local, component-level, specifications of failure. In this paper, the concept of a component failure specification is extended to enable description and reuse of generalized patterns of failure behaviour that are commonly exhibited by components. A language for the description of such patterns is specified, useful patterns are presented and the use of such patterns is demonstrated on an example of a Time-Triggered system. The paper tentatively concludes that careful reuse of failure patterns in conjunction with automated fault tree and FMEA synthesis algorithms can help to rationalize, and simplify, complex safety assessments.