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Human performance deterioration in extreme conditions challenges the viability of critical scenarios during a space mission. Exposure to space flight environment, including microgravity appears to increase the stress on the sensory-motor controls regulatory system in the brain because it is calibrated to operate under gravity. Any pre-existing central dysfunction can allow an input overload which can cascade to and alter other related functions down the functional hierarchy, such as physical (fine postural control, coordination and dexterity, strength, reaction time, fatigue, space perception/orientation) cognitive(trajectory control, attention and vigilance, time awareness, decision making, concentration, and memory), and emotional (motivation, self-control, calmness/aggressiveness). This phenomenon has direct influence on an individual’s tendency for “error proneness”.

The turbopropeller transfers mechanical energy from the flow of a working fluid to that of a momentum medium. The same transfer can be effected more directly by pressure exchange, that is, through the work of mutually exerted pressure forces at appropriately generated interfaces between the two flows. The main drawback of pressure exchangers is that they are of necessity nonsteady-flow machines, highly time-sensitive and not easily controlled. This difficulty is overcome in the “bladeless propeller,” a pressure exchanger whose flow processes, although nonsteady in the frame of reference in which they are utilized, admit a frame of reference in which they are steady. Available theories and experimental results indicate that this device promises to combine an attractive efficiency with advantages of compactness and mechanical simplicity.

The Smart VOV™ is a mechanically programmable variable orifice valve ( VOV ) designed to replace the fixed orifice tube used in CCOT ( cycling clutch orifice tube ) automotive air conditioning systems. The VOV decreases suction pressure, reduces a/c discharge air temperature, and provides cooler vehicle interior temperatures relative to a fixed orifice over a wide range of operating conditions. The VOV is also engineered to minimize system equalization noise. This paper describes the VOV development objectives, the key operating principles, and includes wind tunnel, laboratory, and field test results for CCOT systems as well as a TXV ( thermal expansion valve ) performance comparison.

The electronically controlled transmission has evolved to improve vehicle driveability, shift quality and fuel efficiency. The transmission's computer relies on sensing and modulating fluid pressure for diagnostic and control functions. A Pressure Switch Manifold (PSM) has been developed to sense the pressures in selected hydraulic circuits, providing the computer with PRNDL position and clutch fill information. The device consists of multiple compact snap acting pressure switches electrically interconnected on asingle assembly. The manifold mountsdirectly to the valvebody, with the switches coupled to the appropriate fluid channels. In applications where the PSM is submerged in oil, a thermistor is designed in to provide for temperature sensing. This paper describes the design, performance and application of the pressure switch manifold.

Wheel hubs typically are set in vehicles through nuts with self-locking feature to assure safety. That feature may be done by an external component like a cotter pin, a deformable element incorporated to the nut like polyamide or metallic insert or some controlled mechanical deformation applied right on nut body. Nuts with some self-locking elements are being used in order to eliminate cotter pins from the system. However, during the maintenance of vehicles, some disadvantages appear like damage in thread axle due disassembling, considering controlled mechanical deformation nuts or the replacement of nut with polyamide insert to assure self-lock featuring. This paper presents a solution to replace a fastening in a current front and rear wheel-hub for a passenger vehicle. The study is made comparing a current solution, a controlled mechanical deformed nut - stover type - from a polyamide insert nut and an innovative prevailing torque nut with incorporated washer.

The evaluation of perceived comfort inside a car during the early stages of the design process is still an open issue. Modern technologies like CAE (Computer Aided Engineering) and DHM (Digital Human Modeling) already offer several tools for a preventive evaluation of ergonomic parameters for car drivers using detailed CAD (Computer Aided Design) models of car interiors and by a MBS (multi-body-system) solver for evaluating movements and interactions. Such evaluations are, nonetheless, not sufficient because the subjectivity of comfort perception is due to factors that are very difficult to evaluate in the early stage of design. Physical prototypes are needed and these are often too expensive to be realized.

Traffic crashes are recognized as a major public health problem posing significant threat across the age spectrum. Failure to wear safety belts is among the highest behavioral risk factors identified in numerous health surveys. Because traffic crashes are one of the leading cause of productive years of life lost and the leading cause of death among ages 5-34, effective safety belt and child safety seat promotion programs must involve health as well as highway safety agencies. Health promotion approaches found effective in reducing morbidity and mortality from chronic diseases should be applied in reducing premature death and disability from motor vehicle trauma. Programs and educational approaches in which safety belt and child safety seat use is promoted as a preventive health practice encourage the public to view these protective behaviors as part of a healthy lifestyle.

A full vehicle of a preview control semi-active suspension system based on an interval type-2 fuzzy controller design using a magnetorheological (MR) damper to improve ride comfort is investigated in this paper. It is integrated with the force distribution system to obtain the optimal rate of road adhesion during braking and handling. The nonlinear suspension model is derived by considering vertical, pitch, and roll motions. The preview interval type-2 fuzzy technique is designed as a system controller, and it is attached with a Signum function method as a damper controller to turn on the voltage for the MR damper. This voltage is adjusted for each wheel based on the external excitation generated by road roughness in order to enhance ride comfort. To describe the effectiveness and adaptable responses of the preview controlled semi-active system, the performance is compared with both the passive and MR passive suspension systems during time and frequency domains.

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A newly designed opposed free piston internal combustion hydraulic power generator is proposed in this paper. The pressure of the hydraulic power output of the proposed hydraulic power generator is substantially constant and the hydraulic flow rate is variable. The frequency of free piston changes from zero to maximum in response to the hydraulic flow rate and each gas cycle is always performed under an optimum working condition independent of the power output. If the proposed hydraulic power generator is combined with a variable displacement hydraulic motor, it will be possible to obtain excellent torque-speed characteristic, easy operation, and superior fuel economy. A fundamental test apparatus was constructed and tested in this work. The test apparatus uses an opposed free piston, two stroke cycle, direct fuel injection, and compression ignition engine.

Today's sophisticated aircraft are required to effectively perform a variety of missions. With the advent of micro-miniaturization in electronics and advanced digital computers, a new generation of avionics equipment and systems can be utilized to increase the capabilities of the aircraft. As the quantity and variety of equipment and functions increases, the problems of inter-connecting these equipments with wires presents a constraint on size, weight, signal conditioning, reliability, maintainability and electromagnetic control. Conventional wiring has resulted in large bundles of wires and many connectors which adds excessive weight and reduces the space available for the pilot and other vital elements. This limitation can be relieved significantly by the application of well proven multiplexing techniques.

Motor vehicle accident reconstruction has become a very recognized and essential part of the extensions and applications of engineering training. This is due to the increasing litigious trends of our society. This paper begins by defining a motor vehicle accident reconstruction and proceeds to discuss the qualifications and responsibilities of an accident reconstructionist. Additionally, considerable emphasis is placed upon defining procedures for performing the various tasks that are involved in a reconstruction. Also, the initial investigation, the litigation process and ultimately the rendering of expert witness testimony at the trial are discussed.

This research was to model a 6×4 tractor-trailer rig using TruckSim and simulate severe braking maneuvers with hardware in the loop and software in the loop simulations. For the hardware in the loop simulation (HIL), the tractor model was integrated with a 4s4m anti-lock braking system (ABS) and straight line braking tests were conducted. In developing the model, over 100 vehicle parameters were acquired from a real production tractor and entered into TruckSim. For the HIL simulation, the hardware consisted of a 4s4m ABS braking system with six brake chambers, four modulators, a treadle and an electronic control unit (ECU). A dSPACE simulator was used as the “interface” between the TruckSim computer model and the hardware.

Much has been written over the years regarding the advantages of using microcellular polyurethane (MPU) within the area of chassis and suspension systems. However, there have been limited discussions in an open forum of the geometric design requirements for MPU jounce bumpers. The objective of this paper is to provide a primer for MPU jounce bumper design for engineers working in the chassis and suspension field. Geometric design principles and the effects on manufacturability and durability will be presented to systematically show the limitations and advantages of MPU technology in creating a final jounce bumper design.

Light Duty Vehicle corporate average fuel economy (CAFE), fuel economy label, and greenhouse gas (GHG) requirements are related but are very different. The fundamentals to obtain the data are the same, but to derive the required values, the final formulas have different components. These formulas, how to obtain the values which comprise the formulas, and how to use the test output to obtain the final result necessary to determine compliance with the standards are in regulations, but are not easily located. The information is contained in many documents; such as various sections in the Code of Federal Regulations, U.S. Environmental Protection Agency (EPA) Guidance documents, SAE International papers, American Society of Testing and Materials standards, and law suit judgments. This paper compiles the fundamentals of vehicle CAFE, fuel economy label, and GHG information. The intent is to provide a reference to the foundation of these requirements.

A simple, linear vehicle model is presented which incorporates the most important characteristics of contemporary passenger cars. It is a three mass model with a fixed, inclined roll axis and linear suspension geometric and compliance characteristics. Basic concepts of understeer and oversteer are presented. Static and dynamic requirements are examined, yielding expressions relating the car's design to tire lateral load transfer, total lateral force, and turn radius. Turn kinematics give expressions for the front steer angle and sideslip angle. Suspension geometric and compliance effects describe the rear steer angle, tire inclination angles, and steering wheel angle divided by the overall steering ratio.

Potential regulations surrounding the development, testing and commercial launch of Highly Automated Vehicles and possible liability exposure for the manufacturing and operation of Highly Automated Vehicles are fluid and changing areas, that will continue to evolve over the next several years. The first half of this course reviews where regulations are at the state and federal levels, what actions are currently under consideration, how current regulations will need to change to accommodate HAV’s, and how and when new regulations might be implemented. The second half covers both common law and strict liability and how it may apply to HAV’s.

The reconstruction of a rollover accident is a complex and challenging problem. The analysis and reconstruction of these accidents requires one to investigate various phases of the accident. They include the pre-trip, trip and post-trip phases as well as the occupant kinematics. A good presentation of the reconstruction is essential and requires proper graphical aids, scale models and perhaps animation. It is the purpose of this paper to introduce reconstruction analysis techniques and presentation procedures that will address the various phases of a rollover accident and assist the analyst in his reconstruction and presentation.

The absence of combustion engine noise pushes increasingly attention to the sound generation from other, even much weaker, sources in the acoustic design of electric vehicles. The present work focusses on the numerical computation of flow induced noise, typically emerging in components of flow guiding devices in electro-mobile applications. The method of Large-Eddy Simulation (LES) represents a powerful technique for capturing most part of the turbulent fluctuating motion, which qualifies this approach as a highly reliable candidate for providing a sufficiently accurate level of description of the flow induced generation of sound. Considering the generic test configuration of turbulent pipe flow, the present study investigates in particular the scope and the limits of incompressible Large-Eddy Simulation in predicting the evolution of turbulent sound sources to be supplied as source terms into the acoustic analogy of Lighthill.

Today's competitive market requires new products to have extremely high Quality; customer expectation demands it. Testing, Validation, Setting Requirements, Failure Mode & Effect Analysis (FMEA), and Design Reviews by themselves do not improve a product; they only provide information that has to be translated into Design/Manufacturing & Service tasks. The quality of these tasks determines how well the new product will perform at its introduction. This paper outlines a generic Development Process through the use of an automotive example for a Door Glass Guidance Mechanism. This process includes the fundamental steps involving recommendations for setting requirements, benchmarking, and a methodology on how to design in requirements through the use of analytical and experimental tools to create Robust Designs. Also included are examples of Validation and Assessment Plans that are requirement driven.