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The rapid increase in the sophistication of vehicle automation demands development of evaluation protocols tuned to understanding driver-automation interaction. Driving simulators provide a safe and cost-efficient tool for studying driver-automation interaction, and this paper outlines general considerations for simulator-based evaluation protocols. Several challenges confront automation evaluation, including the limited utility of standard measures of driver performance (e.g., standard deviation of lane position), and the need to quantify underlying mental processes associated with situation awareness and trust. Implicitly or explicitly vehicle automation encourages drivers to disengage from driving and engage in other activities. Thus secondary tasks play an important role in both creating representative situations for automation use and misuse, as well as providing embedded measures of driver engagement.

This paper summarizes the results and findings of a program to design, develop, and evaluate actuator rod seals for use in advanced aircraft high-temperature hydraulic systems. The rod seals are intended to function efficiently and reliably for 3000 hr in the temperature range of -40-500 F. Preliminary studies of various material and design combinations showed that a polyimide low-pressure second-stage V-seal in a two-stage configuration had the greatest potential in long-term duty cycle testing in a simulated actuator test system. Modifications of this seal that provided for improved fatigue life and more efficient loading met the test objectives of 20 X 106 short-stroke cycles of operation at 500 F. Severity of this testing was equivalent to 3000 hr of duty cycle operation. The validity of design techniques used to achieve performance goals was shown.

Filled tetrafluoroethylene (TFE) backup rings offer superior resistance to extrusion, wear, deformation and cold flow in dynamic and static O-ring sealing applications. TFE compounds consisting of various concentrations (5 - 60%) of inorganic fillers such as glass, molybdenum disulphide, graphite and bronze are the most commonly used materials for backup rings. An important consideration in the use of these filled materials is that hard mating surfaces be used to minimize abrasive wear. However, recently developed organic-type fillers have extended the utility of filled backup rings to applications involving non-hardenable mating surfaces such as hard anodized aluminum and titanium.

This paper concerns the design, development and evaluation of metallic seals to meet the extreme conditions of temperature and pressure experienced in fluid power systems of advanced aerospace vehicles. The basic principles and design problems that characterize the use of metallic seals are discussed. Single and two-stage rod seals for 4000 psi, -65 F to +1000 F, hydraulic system applications using mineral oil and polyphenyl ether fluids are described. The performance evaluation of metallic and graphite piston rings are included. The selection of rod-gland material combinations and surface coatings are discussed. Static seal configurations for use at 4000 psi and temperatures up to 1000 F are also described.

The frontal crash standard in the USA specifies that the full front of a vehicle impact a rigid barrier. Subsequently, the European Union developed a frontal crash standard that requires 40 percent of the front of a vehicle to impact a deformable barrier. The present study conducted paired crashes of vehicles using the full-frontal barrier procedure and the 40 percent offset deformable barrier procedure. In part, the study was to examine the feasibility of adding an offset test procedure to the frontal crash standard in the USA. Frontal-offset and full-frontal testing was conducted using both the mid-size (50th percentile male Hybrid III) and the small stature (5th percentile female Hybrid III) dummies. Five vehicle models were used in the testing: Dodge Neon, Toyota Camry, Ford Taurus, Chevrolet Venture and Ford Contour. In the crash tests, all dummies were restrained with the available safety belt systems and frontal air bags.

Visteon Automotive Systems has developed an Electro-Hydraulic Power Assist Steering (EHPAS) System. This low-cost system uses conventional hydraulic power steering components with an electrically-driven and electronically-controlled power steering pump. This paper presents the Visteon EHPAS system and its development process. This process began with analytical modeling of the EHPAS system and integration of these models with a two degree of freedom (2DOF) vehicle model. These models were critical for system analysis and control strategy design. The EHPAS system sizing procedure and control strategy performance optimization were verified with the use of a real-time computer designed by Ford Motor Company, and by specially-designed Visteon test benches. Finally, EHPAS equipped test vehicles were tuned for high performance, providing better feel and fuel economy than conventionally equipped base line vehicles.

Increasingly sophisticated vehicle automation can perform steering and speed control, allowing the driver to disengage from driving. However, vehicle automation may not be capable of handling all roadway situations and driver intervention may be required in such situations. The typical approach is to indicate vehicle capability through displays and warnings, but control algorithms can also signal capability. Psychophysical methods can be used to link perceptual experiences to physical stimuli. In this situation, trust is an important perceptual experience related to automation capability that is revealed by the physical stimuli produced by different control algorithms. For instance, precisely centering the vehicle in the lane may indicate a highly capable system, whereas simply keeping the vehicle within lane boundaries may signal diminished capability.

Distracted driving remains a serious risk to motorists in the US and worldwide. Over 3,000 people were killed in 2013 in the US because of distracted driving; and over 420,000 people were injured. A system that can accurately detect distracted driving would potentially be able to alert drivers, bringing their attention back to the primary driving task and potentially saving lives. This paper documents an effort to develop an algorithm that can detect visual distraction using vehicle-based sensor signals such as steering wheel inputs and lane position. Additionally, the vehicle-based algorithm is compared with a version that includes driving-based signals in the form of head tracking data. The algorithms were developed using machine learning techniques and combine a Random Forest model for instantaneous detection with a Hidden Markov model for time series predictions.