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In the general framework of the EU FP7 MAAT project, a novel green air transport architecture is under development. The paper presents the possible architectures for the cabin connections and the transfer modalities for people, crew and freight, for to the European project MAAT. Different architectures have been evaluated setting out to cover the structural and propulsive needs and to enable the transport modes between the Cruiser and the Feeders. The different possibilities are discussed conceptually, by considering the advantages and disadvantages of the presented configurations. The bases for future detailed design and research are established, as through such conceptual study the main parameters are identified and found to affect the general design of both airships and their operability. The aim of this paper is to specify the necessary elements, which are necessary to perform the docking operation by taking into account the prescribed Feeder-Cruiser geometries.

MAAT project is a large airship project presented to the last European 7 Framework Program Transport including Aeronautics 2011 deadline. MAAT project is an airship based cruiser-feeder transport system. This paper analyzes the criticalities of the project and the way to upfront these problems which have different natures and possible solutions. Most important criticalities are analyzed both on a methodological point of view and on a direct point of view. Enhanced design methodologies are analyzed in depth to analyze problems, upgrade the project design status continuously and to examine different design options and solutions. An innovative design method has been defined to avoid that problems can produce show stoppers and minimize time delays during project definition.

The usual laboratory tests of lubricants do not indicate to what degree a given oil may possess the important property of “oiliness,” a property, apparently independent of viscosity, upon which the ability of an oil to maintain lubrication between two surfaces under high pressure seems partly to depend and by which some sort of extremely tenacious and adherent thin layer of oil is held on one of or both the rubbing surfaces so that metal-to-metal contact is in part prevented. Oiliness is of special importance in metal-cutting operations and in some machine parts, such as gear teeth or cams under heavy loads, in which the pressures between the surfaces are far in excess of those permitted in plain bearings. With a view to investigating the behavior of various lubricants, cutting compounds and bearing materials under high bearing-pressures, a special machine has been designed, of which a description is given and data are presented.

This SAE Standard applies to off-road self-propelled construction, forestry and industrial machines as listed in categories 1, 2, and 4 of SAE J1116.

This code applies to mobile work machines and their combinations with mounted and/or trailed equipment.

This SAE Standard lays down the vocabulary and specifies performance test methods and criteria to enable uniform assessment of the service, secondary, and parking brake systems of wheeled specially designed forestry machines. This document applies to self-propelled, rubber-tired special forestry machines defined in SAE J1209 or ISO 6814 as skidders, fellers, forwarders, and the various combinations of these machines.

The results of laboratory investigations and shop experience related to the machining of the alloy systems of columbium, molybdenum, tantalum, and tungsten are presented. Material properties and their relationships to maching characteristics are discussed, as are certain economic aspects of shop practice. Empirical data are presented to illustrate and quantify the more significant characteristics, and conclusions are drawn for appropriate shop maching conditions. In general, these metals are very difficult to machine; the most notable exceptions are the infiltrated forms of tungsten, whose extraordinary maching characteristics approach those of the light metals, and the molybdenum group, which are readily machinable by certain processes. However, grinding any of the refractory metals is slow and difficult, and very smooth finishes are exceedingly difficult to obtain.

THE United States is more independent of outside sources for strategic materials than any other country - and its list of “have-nots” is much shorter than it was in the last World War, Dr. Gillett brings out in this paper - an analysis of just where we stand today as regards ersatz materials. He shows clearly, however, that very definite problems face the United States as regards manganese supplies and substitutes, that tin also is a major worry, and that the situation on chromium “is not so rosy.” Detailing our position in each of the ersatz categories, Dr. Gillett points out that high cards in the ersatz deck may be of several denominations. A “stock-pile” of materials is a high card, but not necessarily a winning one as no one knows how long a war will last. More powerful cards are techniques capable of bringing into use low-grade domestic supplies and/or the creation or existence of domestically available substitutes.

A unique combination of metal chemistry and heat treatment has lead to the invention of MADI (machinable austempered ductile iron). Two MADI grades have been developed: chassis grade for fatigue critical applications and crankshaft grade for high strength applications. The mechanical properties, fatigue life of components and quantitative machinability data of MADI, regular ADI and pearlitic ductile iron are presented. Since the design strength of MADI is 50-100% higher than currently used as-cast ductile irons, significantly lighter weight components can now be produced. MADI may lead the way to the increased use of low cost, ductile iron castings since, for the first time, both improved mechanical properties (fatigue resistance or high strength) and improved machinability have been obtained.

This paper presents a three-dimensional 15-segment model of the Hybrid III dummy for the MADYMO 3D Crash Victim Simulation program. The model is based on measurements conducted on two Hybrid III dummies by Wright Patterson Air Force Base. Results of MADYMO 3D simulations will be compared with Hybrid III sled tests conducted by Ford Motor Co. These tests were conducted at three different impact severity levels. For the three test conditions good agreement between model and experimental results could be observed for most of the output parameters. Recommendations for further model improvements will be made.

Determining injury causation and/or developing injury thresholds is important, specifically in the lumbar spine during minor accidents. Much work has been done to study cervical spine behavior, however, there is a lack of data on injury thresholds of the lumbar spine and on lumbar exposure during these minor events. A MADYMO model was developed to quantify the lumbar loads and accelerations experienced when dropping down onto a surface into a seated position. The model was validated using data collected during tests involving an instrumented Hybrid III dummy. This work shows that MADYMO models can be used to predict the lumbar spine's exposure during common everyday activities.

The International Harmonization Research Activities Pedestrian Safety Working Group (IHRA PSWG) has proposed design requirements for two head-forms for vehicle hood (bonnet) impact testing. This paper discusses the development of MADYMO models representing the IHRA adult and child head-forms, validation of the models against laboratory drop tests, and assessment of the effect of IHRA geometric and mass constraints on the model response by conducting a parameter sensitivity analysis. The models consist of a multibody rigid sphere covered with a finite element modeled vinyl skin. The most important part in developing the MADYMO head-form models was to experimentally determine the material properties of the energy-absorbing portion of the head-form (vinyl skin) and incorporate these properties into MADYMO using a suitable material model. Three material models (linear isotropic, viscoelastic, hyperelastic) were examined.

In this paper four pedestrian models will be presented: three 2-dimensional models with 2, 5 and 7-segments respectively and one 3-dimensional model with 15 segments. All these models were formulated with the general Crash Victim Simulation package MADYMO. Model results will be compared with the experimental results of a Part 572 dummy impacted lateral at two velocities (30 and 40 km/h). The reliability of the models with respect to their complexity will be discussed. Special attention will be given to the mathematical representation of the contact between the pedestrian and sharp vehicle edges and the visualization of the complex 3-dimensional pedestrian motions with a recently developed 3D-Graphics Package.

The objectives of the project is to contribute to reduced emissions by weight reduction, which in this study is made by replacing the inner door steel structure with cast magnesium. Weight target is 55 % relative steel, implying vehicle lightening by more than 25 kg, hence saving 200 litre fuel during the life of the vehicle. A magnesium door concept is expensive in high volumes, and the risks include incomplete die filling, multimetal incompatibility and low strength. Cost efficiency implies to design for integration and commonality. Ductile alloys, correct ingate shape and optimized wall thickness is necessary to meet the impact and quality requirements of the door structure. Joining Al to Mg is mainly limited to adhesives and promising Mg surface treatment alternatives to chromateing have been evaluated.