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Rational design for fire safety necessarily includes consideration of risk tradeoffs that tend to reduce one risk but may increase another. Traditional engineering design criteria can be supplemented with important factors that rely on expertise from other disciplines. Engineering analysis may be able to address reduction in fire risk due to the introduction of new technology, but may not address the social costs associated with this new technology. For example, the resultant increase in vehicle cost may prevent some people from purchasing a vehicle (impacting individuals' lives), may reduce the number of vehicles sold (impacting manufacturers), and may reduce taxes collected (impacting the government). This must be weighed against decreased risk of property damage, injury, and fatality due to fire. In this paper, the methods of benefit-cost analysis from economics were applied to make this evaluation.

An automotive propulsion concept is presented which utilizes liquid nitrogen as the working fluid for an open Rankine cycle. Ambient heat exchangers are used to power an engine that is configured to maximize heat transfer during the expansion stroke. If sufficient heat input during the expansion process can be realized then this cryogenic propulsive system would provide greater automotive ranges and lower operating costs than those of electric vehicles currently being considered for mass production. The feasibility of meeting this engineering challenge has been evaluated and several means of achieving quasi-isothermal expansion are discussed.

In applications ranging from design of customized vehicle interiors to virtual testing of biomedical devices, the processes of modeling, design and analysis involve the simultaneous treatment of artifacts (i.e., parts designed by humans) and anatomical structures. An inherent conflict arises because the geometric descriptions are completely different. Artifact descriptions are typically the output of computer-aided design (CAD) software and consist of a collection of parametric patches that comprise the boundary of the artifact. In stark contrast, the native description of an anatomical structure typically consists of an image stack obtained using a volumetric scanning technology such as computed tomography (CT) or magnetic resonance imaging (MRI). Current practice for simultaneously dealing with both categories of entities involves working primarily in the world of CAD.

Map matching determines which road a vehicle is on based on inaccurate measured locations, such as GPS points. Simple algorithms, such as nearest road matching, fail often. We introduce a new algorithm that finds a sequence of road segments which simultaneously match the measured locations and which are traversable in the time intervals associated with the measurements. The time constraint, implemented with a hidden Markov model, greatly reduces the errors made by nearest road matching. We trained and tested the new algorithm on data taken from a large pool of real drivers.

This paper develops and tests algorithms for predicting the end-to-end route of a vehicle based on GPS observations of the vehicle's past trips. We show that a large portion a typical driver's trips are repeated. Our algorithms exploit this fact for prediction by matching the first part of a driver's current trip with one of the set of previously observed trips. Rather than predicting upcoming road segments, our focus is on making long term predictions of the route. We evaluate our algorithms using a large corpus of real world GPS driving data acquired from observing over 250 drivers for an average of 15.1 days per subject. Our results show how often and how accurately we can predict a driver's route as a function of the distance already driven.

One barrier to the use of algae feedstocks as a source of CO2-neutral, renewable liquid fuel is the potential for high processing costs. An important processing step is the extraction of oil from the biomass. While there is substantial industrial experience in lipids from oil seeds, these processes may be unattractive for algal fuel oil due to high costs. Laboratory data suggest, however, that the relatively fragile nature of algal biomass may speed the mass transfer processes that control the extraction rate, and thus either reduce equipment size or allow increased throughput. In the present paper, laboratory-scale extraction data are used to develop a finite difference model of a full-scale extractor. The results indicate that such an extractor may have an increase in throughput of a factor of 5-10 without losing extraction efficiency.

Oil extracted from microalgae has the potential to offset demand for petroleum, if conditions of cost and scale can be met. In this paper, we present the compositional differences of fatty acid methyl esters (FAMEs) obtained by solvent extraction from two different oleaginous microalgae. Oil samples were extracted from a proprietary alga (Alga X) and a more common Nannochloropsis oculata (NC) using the Soxhlet process with n-hexane. The neutral lipids contained in Alga X comprised approximately 40 to 60% of the algal dry weight, and the oil was mostly converted to methyl esters using a transesterification process. On the other hand, NC produced approximately 25% lipids, but the yield of methyl esters was often less than 1% and subject to high variation. FAMEs were analyzed using gas chromatography and the average chain lengths for NC were shown to be greater than the average chain lengths for Alga X.

A new method for improving the fatigue lives of holes in metal structures has been developed. The StressWave® process provides compressive residual stresses and fatigue life improvement factors that are similar to or exceed those produced by legacy mandrel cold working processes. StressWave creates the stresses prior to machining the hole, without any pre- or extra post-processing operations. The process has been applied in a variety of alloys (aluminum, steel, titanium and cast iron) and section thickness (0.8 to 25 mm). Fatigue testing has shown life improvement factors typically five to twenty times greater than untreated open-hole specimens. Residual stress distributions have been measured by neutron diffraction and photo-elastic techniques and compared with FEA analysis to verify process parameters. Crack growth measurements and fractography have revealed the beneficial compressive residual stresses extend fatigue crack growth life.

This study investigates using driver prediction to anticipate energy usage over a 160-meter look-ahead distance for a series, plug-in, hybrid-electric vehicle to improve conventional thermostatic powertrain control. Driver prediction algorithms utilize a hidden Markov model to predict route and a regression tree to predict speed over the route. Anticipated energy consumption is calculated by integrating force vectors over the look-ahead distance using the predicted incline slope and vehicle speed. Thermostatic powertrain control is improved by supplementing energy produced by the series generator with regenerative braking during events where anticipated energy consumption is negative, typically associated with declines or decelerations.

Whole-body vibration (WBV) is associated with several adverse health and safety outcomes including low-back pain (LBP) and driver fatigue. The objective of this study was to evaluate the efficacy of three commercially-available air-suspension truck seats for reducing truck drivers’ exposures to WBV. Seventeen truck drivers operating over a standardized route were recruited for this study and three commercially-available air suspension seats were evaluated. The predominant, z-axis average weighted vibration (Aw) and Vibration Dose Values (VDV) were calculated and normalized to represent eight hours of truck operation. In addition, the Seat Effective Amplitude Transmissibility (SEAT), the ratio of the seat-measured vibration divided by the floor-measured vibration, was compared across the three seats. One seat had significantly higher on-road WBV exposures whereas there were no differences across seats in off-road WBV exposures.

The University of Washington EcoCAR2 team (UWEC2) is currently in the process of building a Plug-in Hybrid Electric Vehicle (PHEV) for the EcoCAR2 Challenge. This competition challenges 15 universities across North America to reduce the environmental impact of a 2013 Chevrolet Malibu without compromising consumer acceptability. In order to be competitive in EcoCAR2, grid electricity is relied on heavily and the use of the Utility Factor method presented in SAE J2841 - Utility Factor Definitions must be used to compare emissions and consumption results with traditional vehicle results. Powertrain simulation in Autonomie was performed to explore many different hybrid architectures. The simulation results were normalized using the Utility Factor method to reach final architecture and component decisions.

A composite of an aluminum matrix reinforced by short TiNi shape memory alloy (SMA) fibers was fabricated. The processing and thermomechanical behaviors of the composite TiNi/Al6061 were investigated experimentally and analytically. Optimal hot-pressing conditions of TiNi/Al6061 processing were identified. The shape memory effect (SME) was activated by prestraining the composite at the temperature between Ms and As, followed by heating up to Af. SME on mechanical properties, such as microhardness, yield stresses of the composite, were investigated. A computational model for the strengthening mechanism of the short fiber metal matrix composite was utilized to analyze SME on yield stress of the composite. Yield stress of the composite as a function of prestrain was predicted numerically and verified experimentally.

A key to shortening the design cycle is to shorten the initial or conceptual design phase. An enabling technology towards this goal is an architecture called the Design Support System (DSS), which is based on the virtual prototype concept. The DSS combines knowledge with hardware and software into a system that is a model for the design process. It produces a virtual prototype of the design and maintains an intelligent design document, which is automatically updated during the design process. A design domain dependent version for automotive design, known as “Automobile Design Support System” (AutoDSS) was developed in the CADTECH Research Lab at the University of Washington.

Means to extend the range of cryogen (liquid nitrogen or liquid air) powered automobiles via burning a small amount of fossil fuel (gasoline or liquid methane) have been investigated. By utilizing both an ambient air-heat exchanger to vaporize the cryogen and a fossil fuel-fired superheater to elevate the temperature of the gaseous product, the range of the vehicle can be three times that of an ambient-heated propulsion system while not exceeding current ultra-low emission standards. Internal and external combustion power cycles using either liquid air or nitrogen as the working fluid were found to be more fuel efficient than an internal combustion engine operating on the standard Otto cycle. The fuel-cryogen operating expense for the proposed hybrid propulsion systems was found to be higher than that of the conventional automobile; however, the performance calculations were very conservative.

This paper details the development process and model architecture used in the University of Washington's EcoCAR 2 hybrid supervisory controller. The EcoCAR 2 project challenges 15 universities across North America to create a hybrid vehicle that most effectively minimizes emissions and fuel consumption while still maintaining consumer acceptability. The supervisory controller for the University of Washington was designed to distribute torque to the various electric and combustion drive systems on a parallel though the road plug-in hybrid electric vehicle using Simulink and Stateflow. The graphical interface of Simulink offers some distinct advantages over text-based programming languages. However, there are also significant challenges posed by the software, particularly when several controls engineers are working in parallel on a large model with some type of version control.

EcoCAR 2: Plugging in to the Future (EcoCAR) is North America's premier collegiate automotive engineering competition, challenging students with systems-level advanced powertrain design and integration. The three-year Advanced Vehicle Technology Competition (AVTC) series is organized by Argonne National Laboratory, headline sponsored by the U. S. Department of Energy (DOE) and General Motors (GM), and sponsored by more than 30 industry and government leaders. Fifteen university teams from across North America are challenged to reduce the environmental impact of a 2013 Chevrolet Malibu by redesigning the vehicle powertrain without compromising performance, safety, or consumer acceptability. During the three-year program, EcoCAR teams follow a real-world Vehicle Development Process (VDP) modeled after GM's own VDP. The EcoCAR 2 VDP serves as a roadmap for the engineering process of designing, building and refining advanced technology vehicles.

This paper details the control system development process for the University of Washington (UW) EcoCAR 2 team over the three years of the competition. Particular emphasis is placed upon the control system development and validation process executed during Year 3 of the competition in an effort to meet Vehicle Technical Specifications (VTS) established and refined by the team. The EcoCAR 2 competition challenges 15 universities across North America to reduce the environmental impact of a 2013 Chevrolet Malibu without compromising consumer acceptability. The project takes place over a three year design cycle, where teams select a hybrid architecture and fuel choice before defining a set of VTS goals for the vehicle. These VTS are selected based on the desired static and dynamic performance targets to balance fuel consumption and emissions with consumer acceptability requirements.