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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.