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This paper presents the results of the VEST experiment scheduled during the Italian “Marco Polo” Soyuz Mission in April 2002 about which the author was Principal Investigator. VEST is a new integrated system of clothing to be used in the space flight environment. Aim of the experiment was to demonstrate that the provision of a new integrated system of garments to the crew would increase their well being, would allow to collect useful data with less impact on the crew schedule and to prove that in general with VEST equipment less mass and less volume are required for the clothing system. The VEST experiment is the final purpose of the feasibility study in 2001 in order to improve living and working conditions in space by designing innovative fabrics suitable for life inside the International Space Station (ISS) while keeping style a priority.

Remotely operating complex robotic mechanisms in unstructured natural environments is difficult at best. When the communications time delay is large, as for a Mars exploration rover operated from Earth, the difficulties become enormous. Conventional approaches, such as rate control of the rover actuators, are too inefficient and risky. The Intelligent Mechanisms Laboratory at the NASA Ames Research Center has developed over the past four years an architecture for operating science exploration robots in the presence of large communications time delays. The operator interface of this system is called the Virtual Environment Vehicle Interface (VEVI), and draws heavily on Virtual Environment (or Virtual Reality) technology. This paper describes the current operational version of VEVI, which we refer to as version 2.0. In this paper we will describe the VEVI design philosophy and implementation, and will describe some past examples of its use in field science exploration missions.

Vacuum Fluorescent Displays (VFD's) are being used widely as the informational display panel in the automobile because they are a self-emissive, high luminance display device that feature crisp and easy-to-read images. This paper reports on the development of a VFD that can be directly driven by the outputs of a single chip microcomputer operating from a 12 volt supply. This system is most ideal for automotive applications.

VGCF/Carbon composites have been shown to demonstrate high thermal conductivity, comparable to that of CVD diamond, implying utility in high performance electronic packaging. VGCF/carbon composites are unlike diamond in that, typical of most fiber reinforced composites, designed physical properties are incorporated into the composite through fiber architecture. Thermal performance for die cooling is frequently determined by the thermal impedance of the package, measured from the junction to ambient, ϕja, or jucntion to case, ϕjc. This paper reports the results of this test on VGCF/carbon composites with a 1D architecture.

The basic principles and characteristics of VHC (Very High Contrast) LCD technology have previously been introduced and presented. In this paper practical automotive display applications such as a primary instrument display (direct view display), HUD (Head-up display) and virtual image display utilizing this VHC technology are described. Through material development and optical optimization, a highly reflective instrument display, even in a blue-green color was acheived.As well, a high reliability HUD was developed.

This paper deals with a virtual prototyping study, using VHDL-AMS language to model an automotive subsystem and to implement its control scheme. The automotive subsystem under study here is a control system for reference input wheel slip tracking. The control objective is to track a reference input wheel slip. A variable structure sliding mode controller is used to provide robust control of uncertain, often nonlinear, dynamical automotive systems. In this study, the main components of this control system, including the wheel dynamics, sensors, and control logic, are implemented in VHDL-ASM and the complete system is simulated in Simplorer®.

Many kinds of additives such as viscosity index (VI) improvers, anti-wear additives, rust-corrosion inhibitors, antioxides, etc. are added in the lubricant for modern engines. In particular, VI improvers of high molecular weight polymer content are added to base oils to give multigrade oil characteristics against temperature-viscosity sensitivity. However, the incorporation of polymeric additives produces significant decrease of thickening effect by the polymeric additives even at normal operating speed (106s-1) of engine components as well as boundary film formation by the sticking layer of polymeric additives on the solid surfaces. The shear thinning effect of polymeric additives causes serious wear due to reduced film thickness while it may reduces friction forces and the sticky-absorbed polymeric layer protects the surfaces. Abnormally thin film thickness (0.01∼0.1μm) can frequently happen in cam and follower contacts under high fluctuating concentrated loading condition.

Recent researches [1, 2, 3 and 4] showed that the vibration is one of the common occupational risks. The exposition rising to the human body vibration, in hard working that operate tractors, machines diggers and too much vehicles is incomplete, however there are evidences that the regular exhibition to the vibration, can contribute in the pains generation in the back in professional drivers such as, drivers by bus, by tractors and helicopters. According to Griffin [2], to the exhibition to the human body vibration are related to problems in the activity muscular/postural, circulatory system problems and the appearance of inter-muscular disturbances. This way, with the increasing use of off-road vehicles and of new kinds of seats, the acceleration levels investigation and necessary comfort is done, as well as, the dynamic characterization of the same.

ALTHOUGH the problems involved in developing a satisfactory engine-propeller airplane installation using propellers of four or more blades are admittedly more difficult than those encountered with a three-blade propeller, Mr. Guerke points out, a satisfactory installation can be made “if the airplane designer will assume the responsibility of reducing propeller interference effects.” This, of course, may be very difficult if not impossible to accomplish in “pusher” installations, he qualifies. Reporting that two such installations have been made in a normal tractor four-blade installation without recourse to odd blade spacing, he contends that successful installations also can be accomplished in propellers of five or more blades under similar conditions.

Extensive research has been dedicated towards identifying the sources of pollution and the ways and means of mitigating the emission levels to save our planet from alarmingly high pollution levels. It is not exaggeration to say that the petroleum run engines are one of the major contributors to this high pollution levels. For meeting stringent emission legislation, engine has to be optimized for lower emission with better performance. In the recent years, more work is being carried out to reduce NOx emissions from the diesel engines. The present work deals with the development of variable injection cam and the optimization of DI automotive 510cc engine incorporated with VIC (Variable Injection Cam) and the engine performance is studied both analytically and experimentally. Also, it is well established that by diluting the incoming charge with exhaust gases (with EGR technique), the NOx emission could be significantly reduced.

In 2006, the Federal Government, in cooperation with the State of Michigan built an expansive Dedicated Short Range Communications (DSRC) and Wi-Fi network for the purpose of evaluating the Vehicle Infrastructure Integration (VII) network. This developed the need to use safety and mobility oriented applications to test and understand that network. NAVTEQ and Delphi partnered to develop off-board navigation and in-vehicle signage applications, aimed at serving the traveling public, to utilize these networks. As time has progressed, these applications have continued to develop, as one case the market is demanding is Connected Navigation.

Layered structures made from elastic and porous materials are widely used as insulation systems in the automotive industry. They have a dynamic behavior which is strongly influenced by the various interaction mechanisms within the porous material. The paper concentrates on modeling such materials using a 3-D finite element (FE) approach. This model can be combined with a boundary element (BE) procedure in order to assess the radiated acoustic field. The key part of FE representation is a Biot's model for the two phase porous material. A mixed displacement formulation is selected. The model can be used for predicting the surface impedance and/or the acoustic transmission characteristics of layered materials. The combined use of this mixed FE/BE model enables also the evaluation of the acoustic response (radiated power, field pressure).

While on the one hand the development period to meet the market needs to be as short as possible and cost reduction of products is extremely important for manufacturers, the demands for environmental considerations and riders' comfort have recently been rapidly increasing in the area of motorcycle performance as well. Considering these arguments, this paper discusses how to establish technology to predict riders' vibration comfort of a motorcycle, starting from a computer aided design (CAD). So far, only a few papers on the prediction of motorcycle vibration have already been made public, but with regard to modeling the connection between component models even less literature is available and, as a result, empirical figures are widely used. Therefor this paper focuses on the modeling aspects of these connectors to make accurate virtual models that allow the assessment of motorcycle vibrations in operational conditions.

This paper describes Virtual-Hardware-In-the-Loop Simulation (VHILS), a new validation method for real-time control systems. HILS integrates multiple-technology domain simulators and uses no actual hardware components. Target software in binary code formats are executed with CoMET™, a virtual processor platform and physical layer signals are emulated with MATLAB®/Simulink®. Thus, VHILS can replace HILS, which is widely used for control software validation today. The VHILS was applied to the development of adaptive cruise control system (ACCS), and driver maneuvering, vehicle dynamics, microcontroller operation and CAN communication were modeled. The data exchange between multi-domain simulation and communication modeling were identified to be the primary causes of longer computational time.

It can be noted that there is an increasing demand for simple, self-controlling, speed-sensing limited-slip devices with progressive locking characteristics and high torque capacity, in particular in Sport Utility Vehicle and light truck axle and transfer case applications. Existing speed-sensing systems mostly have a degressive locking characteristic curve; other designs are too complex for high volume production. Torque-sensing Limited-Slip Differentials (LSD) that are fully ABS-compatible, provide an insufficient locking effect under extreme surface conditions. Visco-Lok (“the system”) is a new speed-sensing limited-slip device with high-torque progressive engagement and is tuned to minimize driveline windup. This new LSD allows a wide range of calibration in specifying the level of torque transfer at any particular speed difference.

This paper deals with the relationship between the viscosity and Conradson carbon-residues of lubricating-oils for internal-combustion engines. Several curves are established using many grades of the same brands of oil while others are constructed to show this relationship with oils representing everything on the market. Evidence is presented indicating that a true relationship does not exist between the viscosity at any temperature and the carbon-residue value, and sufficient data are presented to show in a general way what can be expected as to the carbon-residue value when the viscosity is known. Limitations are drawn showing which oils can be considered as being, from a carbon-residue standpoint, representative of good commercial products and further, those which have been subjected to drastic refining can be selected.

This paper describes a new tool that provides simultaneous ECU (Electronic Control Unit) bypass rapid prototyping and calibration in an integrated system. In the development of automotive electronic control systems, various calibration tools have long been used to aid in the calibration and verification of control algorithms. In addition, bypass rapid prototyping has become widely used to help speed the development of new control algorithms [1] [2]. MATLAB® and Simulink®, from The MathWorks, Inc. have been widely used as the preferred modeling environment for this rapid prototyping [1] [2]. Until now, no system could provide both the ability to perform bypass rapid prototyping using Simulink and ECU calibration in a single completely integrated system. This paper describes such a system. The system was designed as a co-development effort between Accurate Technologies Inc. and The MathWorks.