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Autonomous vehicles (AVs) have already driven millions of miles on public roads, but even the simplest scenarios have not been certified for safety. Current methodologies for the verification of AV’s decision and control systems attempt to divorce the lower level, short-term trajectory planning and trajectory tracking functions from the behavioral rules-based framework that governs mid-term actions. Such analysis is typically predicated on the discretization of the state space and has several limitations. First, it requires that a conservative buffer be added around obstacles such that many feasible plans are classified as unsafe. Second, the discretized controllers modeled in this analysis require several refinement steps before being implementable on an actual AV, and typically do not allow the specification of comfort-related properties on the trajectories. Consumer-ready AVs use motion planning algorithms that generate smooth trajectories.

Inadequate situation awareness and response are increasingly recognized as prevalent critical errors that lead to young driver crashes. To identify and assess key indicators of young driver performance (including situation awareness), we previously developed and validated a Simulated Driving Assessment (SDA) in which drivers are safely and reproducibly exposed to a set of common and potentially serious crash scenarios. Many of the standardized safety measures can be calculated in near real-time from simulator variables. Assessment of situation awareness, however, largely relies on time-consuming data reduction and video coding. Therefore, the objective of this research was to develop a near real-time automated method for analyzing general direction and location of driver's gaze in order to assess situation awareness.

Driving simulators provide a safe, highly reproducible environment in which to assess driver behavior. Nevertheless, data reduction to standardized metrics can be time-consuming and cumbersome. Further, the validity of the results is challenged by inconsistent definitions of metrics, precluding comparison across studies and integration of data. No established tool has yet been made available and kept current for the systematic reduction of literature-derived safety metrics. The long term goal of this work is to develop DriveLab, a set of widely applicable routines for reducing simulator data to expert-approved metrics. Since Matlab™ is so widely used in the research community, it was chosen as a suitable environment. This paper aims to serve as a case study of data reduction techniques and programming choices that were made for simulator analysis of a specific research project, the Simulated Driving Assessment.

While extensive research points to mechanical injury of the cervical facet joint as a mechanism of whiplash injury, findings remain speculative regarding its potential for causing pain. The purpose of this study was to examine the relationship between facet joint distraction, capsular ligament strain, cellular nociceptive responses, and pain. A novel rat model of in vivo facet joint injury was used to impose C6/C7 joint distraction in separate studies of subcatastrophic and physiologic vertebral distraction, as well as sham procedures. A common clinical measure of behavioral hypersensitivity (allodynia) was measured for 14 days after injury, as quantification of resulting pain symptoms. Also, on day 14, spinal activation of microglia and astrocytes was quantified to examine the potential role of glial activation as a physiologic mechanism of facet-mediated painful injury. Vertebral distractions of 0.90±0.53 mm across the rat facet joint reliably produced symptoms of persistent pain.

To meet the increasing electrical power demands for advanced internal combustion engine (ICE) vehicles, auxiliary power units (APUs) are of growing interest. Fuel cell based APUs offer the potential for high chemical-to-electrical conversion efficiency with low noise and low emissions. It has recently been shown that solid oxide fuel cells (SOFCs) can be used to directly convert the chemical energy of liquid hydrocarbon fuels to electricity. Because the combustion reaction takes place by direct oxidation of vaporized fuel at the fuel cell anode, the expectation exists for development of compact, reformerless APUs that can operate on the same fuel that the ICE uses for vehicle propulsion. Critical issues for the transportation SOFC-APU applications are fast start-up and the need to survive extensive thermal cycling.