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1. On page 111, the authors have described a method to assess driver distraction. In this method, participants maintained a white square size on a forward display by using a game gas pedal of like in car-following situation. The size of the white square is determined by calculating the distance to a virtual lead vehicle. The formulas to correct are used to explain variation of acceleration of the virtual lead vehicle. The authors inadvertently incorporated old formulas they had used previously. In the experiments discussed in the article, the corrected formulas were used. Therefore, there is no change in the results. The following from the article:

A literature review was conducted to survey recent research on the effects of fuel properties on exhaust emissions from gasoline and diesel vehicles, on-road and off-road. Most of the literature has been published in SAE papers, although data have also been reported in other journals and government reports. A full report and database are available from the Coordinating Research Council (www.crcao.org). The review identified areas of agreement and disagreement in the literature and evaluated the adequacy of experimental design and analysis of results. Areas where additional research would be helpful in defining fuel effects are also identified. In many of the research programs carried out to evaluate the effect of new blendstocks, the fuel components were splash blended in fully formulated fuels. This approach makes it extremely difficult to determine the exact cause of the emissions benefit or debit.

The local equivalence ratio, Φ, was measured in fuel jets using laser-induced spontaneous Raman scattering in an optical heavy duty diesel engine. The measurements were performed at 1200 rpm and quarter load (6 bar IMEP). The objective was to study factors influencing soot formation, such as gas entrainment and lift-off position, and to find correlations with engine-out particulate matter (PM) levels. The effects of nozzle hole size, injection pressure, inlet oxygen concentration, and ambient density at TDC were studied. The position of the lift–off region was determined from OH chemiluminescence images of the flame. The liquid penetration length was measured with Mie scattering to ensure that the Raman measurement was performed in the gaseous part of the spray. The local Φ value was successfully measured inside a fuel jet. A surprisingly low correlation coefficient between engine-out PM and the local Φ in the reaction zone were observed.

Recent measurements in transient diesel jets have shown that fuel in the wake of the injection pulse mixes with ambient gases more rapidly than in a steady jet. This rapid mixing after the end of injection (EOI) can create fuel-lean regions near the fuel injector. These lean regions may not burn to completion for conditions where autoignition occurs after EOI, as is typical of low-temperature combustion (LTC) diesel engines. In this study, transient diesel jets are analyzed using a simple one-dimensional jet model. The model predicts that after EOI, a region of increased entrainment, termed the “entrainment wave,” travels downstream at twice the initial jet propagation rate. The entrainment wave increases mixing by up to a factor of three. This entrainment wave is not specific to LTC jets, but rather it is important for both conventional diesel combustion and LTC conditions.

This paper proposes a new returnless LPG fuel supply system designed to increase the efficiency of current LPG engines. With a conventional engine fuel supply system, the fuel pump is driven at a certain speed to pressurize the fuel to an excessive level, and excess fuel that is discharged from the fuel pump but not injected from the injector is returned to the fuel tank via a pressure regulator and a return line. This arrangement keeps the pressure in the fuel supply line at a constant level. Accordingly, during engine idling, fuel cut-off or other times when very little or no fuel is injected from the injector, nearly all the fuel discharged from the fuel pump is returned to the fuel tank via the pressure regulator and return line. Therefore, the energy (electric power) applied to drive the fuel pump is wastefully consumed. Moreover, returning a large amount of excess fuel to the fuel tank can raise the fuel temperature in the tank, causing the fuel to evaporate.

A dual piston Variable Compression Ratio (VCR) engine has been newly developed. This compact VCR system uses the inertia force and hydraulic pressure accompanying the reciprocating motion of the piston to raise and lower the outer piston and switches the compression ratio in two stages. For the torque characteristic enhancement and the knocking prevention when the compression ratio is being switched, it is necessary to carry out engine controls based on accurate compression ratio judgment. In order to accurately judge compression ratio switching timing, a control system employing the Hidden Markov Model (HMM) was used to analyze vibration generated during the compression ratio switching. Also, in order to realize smooth torque characteristics, an ignition timing control system that separately controls each cylinder and simultaneously performs knocking control was constructed.

A generalized MADYMO minor rear crash vehicle model with BioRIDII ATD was developed and validated using the mean response of previously published 12 km/h delta-V rear crash tests. BioRIDII simulation pelvis, thorax and head x-axis accelerations, as well as head y-axis angular acceleration, fell within corridors defining +/- one standard deviation of the mean BioRIDII crash test responses. Peak sagittal plane BioRIDII upper neck forces and moments in the simulation were on par with the mean values observed from the crash tests. After the model was validated for 12 km/h delta-V, the model was further exercised by performing simulations with (1) a Hybrid III 50th percentile occupant and (2) by reducing the pulse by 40% of its original value. Results indicate that this generalized minor rear crash model could be useful in accurately estimating occupant kinematics and kinetics in minor crashes up to at least 12 km/h delta-V as an alternative to expensive and time consuming crash testing.

Herschel and Planck satellites have recently undergone the thermal vacuum and thermal balance (TVTB) test which was performed in the ESA-ESTEC Large Space Simulator for Herschel and in Centre Spatial de Liège (CSL) for Planck. One of the specific targets of the Herschel test was the verification of the thermal stability of two HIFI units (required to be better than 3.10−4 °C/s) and of the Star Tracker mounting plate (required to be better than 2.5.10−3 °C/s), with particular attention on the performance of the relevant feedback control loops. Control system design and model predictions are presented and compared against the test results. Further discussion on the requirement verification is provided.

The International Space Station (ISS) requires advanced life support to continue its mission as a permanently-manned space laboratory and to reduce logistic resupply requirements as the Space Shuttle retires from service. Additionally, as humans reach to explore the moon and Mars, advanced vehicles and extraterrestrial bases will rely on life support systems that feature in-situ resource utilization to minimize launch weight and enhance mission capability. An obvious goal is the development of advanced systems that meet the requirements of both mission scenarios to reduce development costs by deploying common modules. A high pressure oxygen generating assembly (HPOGA) utilizing a high differential pressure (HDP) water electrolysis cell stack can provide a recharge capability for the high pressure oxygen storage tanks on-board the ISS independently of the Space Shuttle as well as offer a pathway for advanced life support equipment for future manned space exploration missions.

This paper focuses on full body dynamical analysis of car ingress/egress motion. It aims at proposing an experimental protocol adapted for analysing joint loads using inverse dynamics. Two preliminary studies were first performed in order to 1/ define the main driver/car interactions so as to allow measuring the contact forces at all possible contact zones and 2/ identify the design parameters that mainly influence the discomfort. In order to verify the feasibility of the protocol, a laboratory study was carried out, during which two subjects tested two car configurations. The experimental equipment was composed of a variable car mock-up, an optoelectronic motion tracking system, two 6D-force plates installed on the ground next to the doorframe and on the car floor, a 6D-Force sensor between the steering wheel and the steering column, and two pressure maps on the seat. Motions were reconstructed from measured surface markers trajectories using inverse kinematics.

The Soft X-Ray Telescope (SXT) is an instrument on the International X-Ray Observatory (IXO). Its flight mirror assembly (FMA) has a single mirror configuration that includes a 3.3 m diameter and 0.93 m tall mirror assembly. It consists of 24 outer modules, 24 middle modules and 12 inner modules. Each module includes more than 200 mirror segments. There are a total of nearly 14, 000 mirror segments. The operating temperature requirement of the SXT FMA is 20°C. The spatial temperature gradient requirement between the FMA modules is ±1°C or smaller. The spatial temperature gradient requirement within a module is ±0.5°C. This paper presents thermal design considerations to meet these stringent thermal requirements.

Humidity control within confined spaces is of great importance for current NASA environmental control systems and future exploration applications. The engineered multifunction surfaces (MFS) developed by ORBITEC is a technology that produces hydrophilic and antimicrobial surface properties on a variety of substrate materials. These properties combined with capillary geometry create the basis for a passive condensing heat exchanger (CHX) for applications in reduced gravity environments, eliminating the need for mechanical separators and particulate-based coatings. The technology may also be used to produce hydrophilic and biocidal surface properties on a range of materials for a variety of applications where bacteria and biofilms proliferate, and surface wetting is beneficial.

{ Natural fibre-reinforced composite has the potential to replace current materials used for automotive industrial applications. Oilseed flax fibre could be used as reinforcement for composites because it is readily available, environmentally friendly and possesses good mechanical properties. In this research, oilseed flax fibre reinforced-LLDPE and -HDPE biocomposites were developed through extrusion and injection molding. The flax fibre was chemically treated to improve the bond between the fibre and polymer. Flax fibre was mixed with low linear density polyethylene (LLDPE) and high density polyethylene (HDPE) with fibre content varying from 10 to 30% by mass and processed by extrusion and injection molding to biocomposites. The mechanical properties, surface properties, and thermal properties of biocomposites were measured to analyze the treatment and processing effect and to compare the effect of different flax fibre concentrations on the biocomposites.

The cost of human natural language translation of Service Information, Assembly Instructions, Training Materials, Operator Manuals and other similar documents is a major expense for manufacturers. One translation avoidance method involves replacing most of a document’s text with still and/or animated graphics. While the graphics with minimum text concept has savings potential, clarity of communication must be maintained for widespread application of this technique. The necessary clarity should be achieved if standards are established for the symbols and graphical conventions used. This paper provides an example of a repair procedure documented using the graphics with minimum text paradigm, describes many of the anticipated standards and provides an update on the progress towards achieving a standard development project.

Many engineers have been working to reduce brake noise in many ways for a long time. So far, a progress has been made in preventing and predicting brake noise. Nevertheless, there are some discrepancies of brake noise generation propensity between testing for the prototype and the production. As known in general, the reason for this unpredicted brake noise occurrence in production is partly due to the variation of the resonant frequency, material and the other unpredictable or unmanageable variations of the components in a brake system. In this paper, effects of chemical components and casting process of gray iron brake disc on its resonant frequency variation have been studied. Especially this paper is focused on the variation in material aspects and manufacturing parameters during disc casting in usual production condition. And their effects are investigated by the variation of out-of-plane modal resonant frequency.

The effectiveness of serial link articulated robots in aerospace drilling and fastening is largely limited by positional accuracy. Unguided production robotic systems are practically limited to +/-0.5mm, whereas the majority of aerospace applications call for tolerances in the +/-0.25mm range. The precision with which holes are placed on an aircraft structure is affected by two main criteria; the volumetric accuracy of the positioner, and how the system is affected when an external load is applied. Production use and testing of off-the-shelf robots has highlighted the major contributor to reduced stiffness and accuracy as being error ahead of the joint position feedback such as backlash and belt stretch. These factors affect the omni-directional repeatability, thus limiting accuracy, and also contribute to deflection of the tool point when process forces are applied.

This paper describes the joint development by Tenneco and Pi Shurlok of a complete diesel engine aftertreatment system for controlling particulate matter emissions. The system consists of a DOC, DPF, sensors, controller and an exhaust fuel injection system to allow active DPF regeneration. The mechanical components were designed for flow uniformity, low backpressure and component durability. The overall package is intended as a complete PM control system solution for OEMs, which does not require any significant additions to the OEM's engine control strategies and minimizes integration complexity. Thus, to make it easier to adapt to different engine platforms, ranging from small off-road vehicle engines to large locomotive engines, model-based control algorithms were developed in preference to map-based controls.

A driving simulator capable of duplicating the critical sensations incurred during a spin, or when a driver is engaged in drift cornering, was constructed by Mitsubishi Heavy Industries, Ltd., and Hiromichi Nozaki of Kogakuin University. Specifically, the simulator allows independent movement along three degrees of freedom and is capable of exhibiting extreme yaw and lateral acceleration behaviors. Utilizing this simulator, the control characteristics of drift cornering have become better understood. For example, after a J-turn behavior experiment involving yaw angle velocity at the moment when the drivers attention transitions to resuming straight ahead driving, it is now understood that there are major changes in driver behavior in circumstances when simulator motions are turned off, when only lateral acceleration motion is applied, when only yaw motion is applied, and when combined motions (yaw + lateral acceleration) are applied.

The presented paper introduces the new software complex aimed at simulation of the riveting process as applied to aircraft parts. The software complex implements the novel mathematical model based on minimization of the potential energy. The paper gives the detailed description of the mathematical model and particularizes the main features of the software. The physical and numerical tests aimed at validation of the software are also described in the paper.

Manual drilling and Lockbolt installation in carbon fiber structures is a labor intensive process. To reduce man hour requirements while concurrently improving throughput and process quality levels BROETJE-Automation developed a gantry positioning system with high performance multi-function end effectors for this application. This paper presents a unique solution featuring fully automated drilling and Lockbolt installation (inclusive of automated collar installation) for the vertical tail plane (vertical stabilizer) of large commercial aircraft. A flexible and reconfigurable assembly jig facilitates high access of the end effectors and increases the equipment efficiency. The described system fulfils the demand for affordable yet flexible precision manufacturing with the capacity to handle different aircraft model panels within the work envelope.